Joint contractures in patients with juvenile diabetes and their siblings.

Six hundred fifteen children (310 with diabetes, 106 nondiabetic siblings, and 199 nonsibling controls) were examined for the presence of joint contractures. Forty children had contractures: 8.4 per cent of those with diabetes and 4.6 per cent of those without diabetes. Contractures were present, however, in 9.4 per cent of nondiabetic siblings, and only 2 per cent of nonsibling controls, suggesting a familial tendency to joint contractures. The older the patient, the more likely he was to have contractures. There was no correlation with sex, race, or age at onset of the disease.


[Indications for the location of trabeculotomy in simple glaucoma. II. The demonstration of aqueous outflow with fluorescein].

Iontophoresis is less apt to prove the existence of outflow channels of aqueous humour, but it is appropriate in demonstrating filtering blebs. After injecting fluorescein directly into the anterior chamber, the outflow channels are clearly marked in enucleated non-glaucomatous eyes, as well as in eyes containing a tumor, prior to enucleation. Regularly, one is able to observe sectors in which the aqueous veins are filled slowly or not filled at all. Injecting fluorescein directly in Schlemm's canal proves that in cadaver eyes without glaucoma the lumen is open all around. Sectorial filling defects of vessels leading out of Schlemm's canal are often seen. In three patients with simple glaucoma blocking of dye was noticed during passage through Schlemm's canal without reappearance. Our experiments give the impression that segmental division of Schlemm's canal is more marked in eyes with glaucoma than in normal eyes. If local occlusions within Schlemm's canal are of importance for the range of lowering of intraocular pressure, one must differentiate between the trabecular and the intrascleral part of the resistance of outflow in the operation field, in order to choose the best operating procedure. Such a differentiation seems, in principle, possible using fluorescein--primarily injected into the anterior chamber directly, and secondarily into a given part of Schlemm's canal.


Recent developments in the treatment of obesity with particular reference to semistarvation ketogenic regimens.

Three new techniques have been developed for the treatment of obesity--behavior modification, semistarvation ketogenic regimens, and surgical therapy. Behavior modification appears to be effective for weight maintenance after weight loss through balanced deficit dieting for patients at less than 130 per cent of desirable body weight and semistarvation ketogenic regimens for patients from 130 to 200 per cent of desirable body weight. When indicated, surgical therapy is more efficacious for patients who are in excess of 200 per cent desirable body weight. All three approaches should be considered experimental until a larger experience is acquired and preliminary results are confirmed.


[Rebound regression after additional hormonal treatment with ethinyl oestradiol of metastasising carcinoma of the breast in females: frequency and clinical significance (author's transl)].

Rebound regression occurred in 13 of 42 females (30.9% with metastasising carcinoma of the breast in the postmenopausal period in whom additional hormonal treatment with ethinyl oestradiol had brought about a remission. Duration of the rebound response ranged from 3 to 44 months (average 11.2 months; mean 8 months). There was a significantly longer duration of remission (18.7 months compared with 12.0 months; P = 0.01) in patients with than those without a rebound response. There was also a significant correlation between the duration of the preceding remission under additional hormonal treatment and the duration of the subsequent rebound response (P less than 0.01). On the other hand, there was a negative but not significant correlation between the free interval duration which preceded the metastasisation and the duration of the rebound regression.


[Human diploid cell (HDC) rabies vaccine immunoprophylaxis in persons at risk (author's transl)].

Twenty persons working in the institute testing rabies vaccines and sera were vaccinated three times at monthly intervals with HDC rabies vaccine. In 9 persons in whom the basic immunisation was completed more than two years previously a booster dose was given. The antibodies formed after vaccination were measured in international units (IU). Serum antibody levels rose constantly during the basic immunisation period. Four weeks after the second vaccination definite sero-conversion could be demonstrated in all persons, the mean antibody level was 6.05 IU/ml. The antibody level rose after the third vaccination to a mean of 10.7 IU/ml and sank over the following six months to 1.5 IU/ml. Two years later the mean level was 0.5 IU/ml. After boostering the antibody level rose to 29.6 IU/ml within a week and after two weeks reached one hundred fold the original level. In view of these results which agree with other studies reexamination of the present vaccination scheme for prophylactic rabies vaccination is recommended.


[Results of using the reflomat for determining glucose concentration, and the influence of glycolysis inhibitors on Reflotest-glucose (author's transl)].

There was a close correlation between the hexokinase-glucose-6-phosphate-dehydrogenase method and reflomat/Reflotest-glucose on capillary blood samples without addition of glycolysis-inhibitors. The relative deviations were less than 10% over the entire range. In systematic studies set up to determine the influence of sodium fluoride and sodium monoiodo-acetate on the reflomat/Reflotest glucose system it was demonstrated that sodium monoiodo-acetate can be used when determining glucose with reflomat/Reflotest glucose, while sodium fluoride produced false values with this system.


[Familial bilateral renal-cell carcinoma and cerebellar haemangioma (author's transl)].

In three brothers of a family with a high incidence of cancer a bilateral renal-cell carcinoma was demonstrated. In the index case there was also a cerebellar haemangioblastoma. At necropsy primary bilateral renal-cell carcinoma was demonstrated while intrarenal metastases were excluded. The cases are considered to be predominantly renal manifestations of the von Hippel-Lindau syndrome with facultative oculocerebellar involvement. Urological and cytogenetic study of other family members provided no evidence of further manifestations of the syndrome. Clinical supervision of members of such families is indicated.


[Duration of protection after BCG vaccination with the 1331 Copenhagen strain (author's transl)].

Children vaccinated in 1975 with different doses of BCG were tested when they were 2 1/2 years old by means of the tine test or, if negative, the tuberculin test at 1 : 100. Of those children who, according to present-day view, had been satisfactorily immunised, 34 of 42 still showed a tuberculin allergy after 2 1/2 years, of those unsatisfactorily vaccinated only 23 of 38. In addition it was found that, contrary to general teaching, positive tuberculin allergy is possible even without scar after a BCG vaccination with the Copenhagen strain (6 of 13). The need of revaccination of tuberculin-negative persons is stressed.


[Recognition of female carriers of haemophilia A (author's transl)].

The detection rate for female carriers of haemophilia A was investigated by comparing the one-step method of Hardisty and Macpherson for biological activity of factor VIII with quantitative immunoelectrophoresis (after Laurell) for factor VIII-associated antigen. Certain or probable positive results were obtained in 25 of 27 female carriers by the quantitative immunoelectrophoresis, but only in 18 when measuring factor VIII activity.


Elastase-inhibitory activity of aortic glycosaminoglycans during cholesterol-induced atherosclerosis.

Elastase-inhibitory activity of aortic glycosaminoglycans, measured in vitro, was found to be significantly reduced in rabbits fed a 2% cholesterol diet for 60, 90, and 120 days. The reduction, suggested to be due to alteration in the composition of aortic glycosaminoglycans, may be relevant to the process of atherogenesis.


Variation in the response of plasma enzyme activities in avian species dosed with carbophenothion.

The response of various species of Anser and Branta geese and other avian species to the ingestion of carbophenothion (S-[[(4-chlorophenyl)thio]methyl] O,O-diethyl phosphorodithioate) has been investigated. Optimum assay conditions for measurement of glutamate oxaloacetate transaminase, glutamate dehydrogenase, sorbitol dehydrogenase, and cholinesterase in avian plasma were developed for the study. The administration of acutely toxic doses of carbophenothion to Japanese quail, pigeons, and chickens, and to Greylag, Pink-footed, Greenland White-fronted, and Canada geese led to species-dependent responses for both plasma glutamate oxaloacetate transaminase and cholinesterase levels. Carbophenothion administered to Japanese quail at several dose levels produced changes in plasma enzyme levels which were dependent on dose and time. The level of plasma glutamate oxaloacetate transaminase after dosing in the Anser family of geese rose more rapidly than in the Branta species but no change was found in this enzyme in either chickens or pigeons. In contrast to geese and pigeons, chickens exhibited no plasma cholinesterase inhibition for 3 hr after dosing. These enzyme changes demonstrate a species variation in the toxicological response of birds to a pesticide and indicate the desirability of using more than one avian species for pesticide toxicity testing.


[Early effect of adrenalectomy and castration on the demethylating activity of the liver microsomal fraction in male rats].

The author examines three indices in liver microsomal fraction during the first five days after castration and adrenalectomy of male rats: demethylation in vitro of amidophen, amount of cytochrome P450 and cytochrome b5. Demethylating activity is lowered significantly to the respective control on the second day after adrenalectomy--73%, on the fifth day--61%; after castration on the third day--71%, on the fifth day--75%; after simultaneous castration and adrenalectomy after two days--53%, but on the fifth day--22%. The amount of cytochrome P450 diminishes parallely to the demethylating activity is due to the reduced amount of cytochrome P450, but the reduction of the latter is explained by the lowered activity of aminolevulanatsynthetase--the limiting enzyme in the synthesis of heme of cytochrome P450. Androgens and corticoids are inductors of microsomal oxidative enzymes and probably on the basis of this action the activity of aminoevulinatsynthetase is affected.


[Enzymatic activity in the uterine musculature of rats after castration and testosterone treatment].

The authors examined the activity of GOT, GPT, LDH and ALD in the myometrium of ovariectomized female rats, treated with testosterone. There was a eduction in the activity of the examined enzymes in both experimental groups of animals in comparison with the group of healthy rats. The reduction of the enzymic myometrial activity was considerably more manifested in the group of ovariectomized rats than in those treated with testosterone. The results were interpreted as a consequence of the reduced synthesis of proteins enzymes due to insufficient estrogen stimulation in the myometrial tissue, sensitive to estrogen. There was a possibility also that the reduction of the enzymic synthesis was caused by energetic deficit on account of insufficient transhydrogenase activity as a result of the reduced estrogen concentrations.


[Effect of triquinol on the central nervous system].

The authors examined the influence of the preparation triquinol on the function of the central nervous system, using neuropharmacological and electrophysiological methods. Traquinol in small doses revealed slight stimulating central effect, causing uneasiness, increased reaction to touch and pain, slight exophthalmia, These manifestations were accepted as a sign of the sympathycomimetic action of the preparation. The large doses caused myorelaxing phenomena-reduced spontaneous motor activity, muscular tonus, inhibition of the polysynaptic reflexes. Electroencephalographic examinations showed lowering of the threshold for obtaining the reaction of waking during acute experiments and of the threshold for obtaining desynchronization after exteroceptive stimuli. These data could be explained by the sympathycomimetic effect of the preparation.


[Effect of echinopsin and adepren on motor activity in rats].

We have studied the influence of synthesized in NIHFI psychotropic drugs echinopsin and adepren for their locomotor activity on white rats in open field and staircase. Comparative parallel experiments were carried out with psychostimulants and antidepressive drugs utilized in therapeutic practice. We found that echinopsin in low doses increases the locomotor activity and in large doses decreases. Its action in open-field and staircase is different from the effect of amphetamine and coffeine which is confirmed by clinical evidence. Adepren decreases the locomotor activity in single application as a result of decreasing of brain noradrenaline which is similar to the effect of MAOI drugs.


[Experimental study of the changes in a previously damaged and normal myocardium under the influence of hemorrhagic shock].

The authors examined morphologic changes in preliminarily damaged and normal myocardium under the influence of hemorrhagic shock. It was established that the preceding damages of the myocardium (microcicatrixes and organizing microinfarctions) made it more sensitive to acute hypoxia under the conditions of hemorrhagic shock. The electrone microscopic and histologic findings in both groups revealed acute and ischemic damages of the myocardium, manifested in vacuolization and distruction of mitochondria, dilatation of sarcoplasmic reticulum, contracted changes and fuxinophilic necrosis. The morfometric determination of the degree of distribution of fuxinophilic necrosis revealed that they were considerably more manifested under the conditions of hemorrhagic shock on the background of myocardiopathy (p less than 0.001).


[Experimental droperidol protection and treatment of pulmonary edema].

The authors carried out an experimental study of the protective and therapeutic effect of droperydol on 48 rabbits, with adrenaline lung edema. The results from the conducted studies showed that droperydol, administered both prophylacticaly and therapeuticaly, diminished significantly the gravity of lung edema and increased the percentage of survival up to 67.7% (in rats, treated therapeuticaly) and up to 100% (in the rats, treated prophylacticaly), while the survival did not surpass 20% in the control group. These results were better in comparison with the data, found earlier, indicating the effect of chlorasine, which manifested only protective action in rabbits with lung edema and worsened its course, when it was applied therapeuticaly.


[Light microscopic and ultrastructural changes in the myocardium in experimental myocardiopathy in rats].

The authors examined the morphological changes in the myocardium of rats with myocardiopathy, caused by electrolytes, steroids and catecholamines. There were fresh and organized microinfarctions, occupying around 17--18% of the volume of the left heart ventricle. Scattered fuxinophilic necrosis were present in the zones outside the infarctions. The electrone microscopic examination of these areas showed vacuolization and crystolisis of mitochondria, dilatation of cysterns of the sarcoplasmic reticulum after dilatation of Z discs of miofibrils and increased folds with herniation of the intercanicular discs. The obtained model belongs to the group of the infarction-like myocardiopathies and resembles the changes in the human myocardium during involvment of the small intramural myocardial arteries and microcirculatory bed.


Active noncompliance as a cause of uncontrolled seizures.

A 26-year-old woman with intractable seizures and fluctuating plasma phenytoin concentrations is described. Noncompliance with prescribed drug regimens was suspected. Phenytoin was first given as a capsule and then as an elixir. Ingestion of the capsule was monitored, and active non-compliance was proved and admitted by the patient. The causes of inadequate plasma phenytoin concentrations are few and can be determined either by specific laboratory methods or by changing the form of the drug.


Neuropsychological correlates of the electroencephalogram in epileptics: III. Generalized nonepileptiform abnormalities.

A broad battery of neuropsychological tests was given to 111 adult epileptics treated primarily with phenytoin. The patients were grouped according to degree of generalized nonepileptiform EEG abnormalities in waking EEGs. In patients classified as None/Mild, Moderate, or Marked in terms of these EEG abnormalities performances on 15 neuropsychological measures were contrasted. Statistically significant differences across the groups were found on 13 of the 15 neuropsychological variables. An orderly decrease in performance occurred as a correlate of an increase in EEG abnormalities. These results were compared to a similar analysis of the correlates of topographic distribution of epileptiform discharges (Absent, Focal, Generalized). It was discovered that degrees of generalized slow wave EEG abnormalities were more potent in differentiating levels of neuropsychological performance than epileptiform discharges. Nevertheless, when discharges and degree of nonepileptiform abnormalities were simultaneously considered, a maximal level of correlation was reached.


Characterization of pinealectomy induced convulsions in the Mongolian gerbil (Meriones unguiculatus).

The Mongolian gerbil (Meriones unguiculatus) exhibits convulsions after pinealectomy (PX). Included in the convulsions are wild running, tonic-clonic activity, and occasionally death. This paper reports various parameters that influence the convulsions. Animals 60 and 90 days old have a shorter latency to onset of convulsions than do 30-day-old gerbils. Animals pinealectomized at the onset of light (0600) in an LD 14:10 photoperiod have a shorter latency to onset and greater number of convulsions than animals pinealectomized at other times. Modulation of the photoperiod to LD 20:4 and 4:20 does not affect the convulsions. Superior cervical ganglionectomy (SCGX) does not result in convulsions; subsequent PX of the SCGX animals does. Replacement of pineal extract does not prevent the convulsions. The PX induced convulsion in gerbils resembles the parathyroidectomy-pinealectomy induced convulsion in the rat in all aspects, but with a shorter latency to onset.


Elevation of seizure thresholds: a comparison of cerebellar stimulation, phenobarbital, and diphenylhydantoin.

Generalized EEG seizures were induced in acute, conscious New Zealand albino rabbits with intravenous pentylenetetrazol (PTZ) (10 or 15 mg/kg) or electrical stimulation of the frontal cerebral cortex (ELEC) (50 Hz, 1 msec pulse duration, 2 sec train duration, 4.0-7.6 V). Three anticonvulsant treatments were compared: (1) electrical transhemispheral stimulation of the ansiform or simplex cerebellar lobes (10 Hz, 1.5 msec, 3-4 V), (2) phenobarbital (PB) (25 mg/kg, i.v.), and (3) diphenylhydantoin (DPH) (30 mg/kg, i.v.). After treatment, increments in PTZ dose or stimulation voltage were applied until a seizure was evoked that approximated the original in severity and duration. PTZ seizure thresholds were not elevated by DPH, and electrically induced seizure thresholds were not elevated by cerebellar stimulation (CBL). The four remaining seizure threshold elevations (increase in PTZ dose or stimulation voltage) were significant at a level of 0.025 or greater. Comparison of the elevations of seizure thresholds showed no differences at the 0.01 level of significance. Thus, no differences were seen between elevation of PTZ seizure thresholds by CBL or PB, or elevation of electrically induced seizure thresholds by PB or DPH, when examined on an acute basis.


Effect of streptozotocin diabetes and insulin administration on some liver enzyme activities in the post-weaning rat.

Streptozotocin-induced diabetes suppressed the normal development of the nine glycolytic and lipogenic enzyme activities measured. With the exception of NADP-isocitrate dehydrogenase, insulin replacement therapy induced increased activities of the enzymes in streptozotocin-treated rats. Insulin appeared to have a specific effect on the activities of glucokinase, ATP-citrate lyase, malic enzyme, and glucose-6-P-dehydrogenase.


Guanase in reticulocytes and other rat tissues.

A sensitive and precise assay of guanase was based on the conversion of 14C-guanine to uric acid in the presence of excess xanthine oxidase. The enzyme was entirely soluble in rat tissues and no inhibitors of it were detected. The most active tissues were red blood cells, lung and lactating mammary gland, with more than twice the activity of liver. The contained blood could account for the low activity in adult skeletal muscle and some other tissues. All fetal tissues examined were without activity. Activity in mammary gland rose fourfold during lactation and dropped precipitously during involution, with a secondary rise associated in time with the loss of cells from the gland. Reticulocytes present normally and after hemorrhagic anemia appeared to account for substantially all of the high guanase activity in red blood cells. The guanase level could be used to predict the degree of reticulocytosis in rats within confidence limits of +/- 0.2%. The virtual absence of guanase in human red cells was confirmed, even in bloods containing elevated reticulocyte numbers.


Inactivation of rat pancreas amylase during electrophoresis in the presence or absence of urea.

Rat pancreas amylase activity was irreversibly destroyed when subjected to electrophoresis. The measure of enzyme inactivation was dependent on the duration of electrophoresis. In the presence of urea the amylase denaturating effect was enhanced.


The presence of serum creatine kinase 2 (MB) in acromegalic myopathy.

Increase in size of bone is characteristic of acromegaly. In addition, hypertrophy of other tissues including skeletal muscle and associated myopathy may occur. We recently found 10 U/1 of isoenzyme creatine kinase 2 (MB) or 10.9% of total creatine kinase in a patient with acromegaly who did not show clinical or laboratory evidence of acute myocardial necrosis. The myopathy associated with acromegaly is thus another cause for the presence of serum CK 2 (MB), and CK 2 (MB) is not a specific isoenzyme for myocardial damage since it may be identified in the serum of patients with skeletal muscle conditions.


Release of cryptic monoamine oxidase activity by growth of BHK-21 cells in D-chloramphenicol.

The activity of monoamine oxidase, a marker enzyme of the outer mitochondrial membrane, is stimulated in BHK cells grown in the presence of 100 microgram ml-1 D-chloramphenicol. The observed stimulation can be reversed by removal of the antibiotic. Addition of the non-ionic detergent Triton X-100, to cell homogenates results in an elevation of the enzyme activity similar to that produced by D-chloramphenicol treatment. The activation by chloramphenicol is apparently related to a release of cryptic monoamine oxidase activity.


Metabolic responses of untrained individuals to warm-up.

Seven untrained male subjects were studied for the effects of mild warm-up on oxygen uptake and lactic acid production. Each subject completed two standardized workloads on a bicycle ergometer requiring 75% of their physical work capacity. Protocols of the two tests consisted of either no warm-up or a 4-min warm-up preceding a 5-min exercise at approximately 80% of their maximal oxygen uptake. The contrasting protocols did not reveal any significant differences between heart rate, lactic acid, and oxygen uptake. The dominant influence on the metabolic processes was the absolute workload of the tasks and not the presence or absence of preliminary related activity. It was concluded that an untrained individual lacks the cardiovascular and cellular adaptations necessary to demonstrate metabolic benefits from warm-up.


The effect of age and activity level on simple and choice fractionated response time.

Simple and choice knee extension response time was measured on four groups of subjects: Old Active, Old Inactive, Young Active, and Young Inactive. Each response measure consisted of total reaction time plus movement time. Total reaction time was further fractionated into premotor time, which represents the central processing component, and motor time, which represents the peripheral muscular component. All simple and choice fractionated response components demonstrated an age-related lengthening with motor time showing the least amount of lengthening. Although activity level enhanced the speed of all components in aged subjects, movement time was affected to the greatest extent and motor time was affected the least. It is particularly noteworthy that (1) motor time is so little influenced by age and level of activity and (2) the deterioration in speed of movement with age is almost completely negated in Old Active subjects. The results suggest that a life style of regular physical activity has a beneficial effect on several aspects of performance, especially in regard to speed of movement.


Effect of decreased availability of substrates on intramuscular triglyceride utilization during exercise.

Intramuscular triglycerides mobilization during prolonged physical exercise was examined in rats fed ad libitum, in rats fasted for 24 h and in rats treated with nicotinic acid. It has been found that during exercise the intramuscular triglyceride level was markedly reduced only in the red muscle but not in the white and intermediate muscles. Fasting significantly augmented the utilization of triglycerides in the red muscle during exericse. The post-exercise triglyceride level in the red muscle of the rats treated with nicotinic acid was similar to that in the control group whereas blood FFA level, in the nicotinic acid-treated group was much lower than in the control group. Nicotinic acid increased glycogen utilization in the liver and in the skeletal muscles during exercise. It may be concluded that the major cause of the reduction of the triglyceride level in the red muscle during exercise is a developing shortage of available carbohydrates. The greatly elevated blood FFA level during exercise does not seem to have a sparing effect on the intramuscular triglyceride level during exercise. However, it does spare glycogen content in the liver and the skeletal muscles.


Changes in aerobic fitness and body fat during army recruit training.

Aerobic fitness and related indices were evaluated in 254 soldiers at the beginning and near the end of initial army recruit training. Aerobic fitness in terms of maximal aerobic power was  preidcted from the Astrand-Ryhming submaximal heart rate bicycle test. Estimated VO2 max increased by 8%, 42.0--45.3 ml/kg . min. Accompanying this increase in aerobic capacity was a decline in body fat content without a change in body weight. It is concluded that army recruit training at the time of this study was effective in terms of increasing aerobic work capacity and reducing excess body fat.


Oxygen uptake and blood flow of the lower limb in maximal treadmill and bicycle exercise.

The present study was undertaken to compare the effects of maximal treadmill and bicycle exercise on maximum oxygen uptake and blood flow in the lower extremity. Mean maximum oxygen uptake in maximal treadmill exercise was higher than that in bicycle exercise (p less than 0.001). Mean values and standard errors of blood flow measured immediately after maximal treadmill and bicycle exercise in the thigh were 39.1 +/- 4.0 and 44.2 +/- 2.8 ml/100 ml . min, the difference not being significant. However, a significant difference in blood flow in the calf measured immediately after both types of exercise was observed (p less than 0.001). Blood flow in the thigh immediately after bicycle exercise was significantly higher than that in the calf (p less than 0.001), whereas the difference between thigh and calf in treadmill exercise was small and statistically not significant. Leg blood flow, the average value of blood flow of the thigh and calf added together, was used as an index of blood flow in the lower extremity. It was found that the leg blood flow was significantly higher on the treadmill than with bicycle exercise (p less than 0.05). From these results, it is suggested that the lower maximum oxygen uptake observed during bicycle exercise as compared with treadmill exercise seems to be due to a lower blood flow in the lower limb.


A special thermal stress problem in ceramic industry.

While surveying the hygienic conditions in small to medium ceramic industries, it was noted that an acute thermal stress problem existed in kiln unloading operations being performed manually. A more detailed investigation of this problem in four typical ceramic factories confirmed that the thermal conditions imposed severe stress on the workers with WBGT values ranging between 43 and 54 degree C inside the kiln. However, the physiological strain experienced by even the workers who remain inside the kiln for unloading the saggers for 10 min or more at a tiem before coming out for a spell of rest was not excessive, except in a few cases. This suggests that the workers had fortuitously chosen, perhaps by experience, a work-rest schedule which did not prove too strenuous. It is considered that it would be desirable to regulate this operation in each factory on a systematic manner after necessary studies to rationalize the work-rest procedure.


ADP-ribosylated histone H1 from HeLa cultures. Fundamental differences to (ADP-ribose)n-histone H1 conjugates formed into vitro.

ADP-ribosylated histone H1 was isolated from intact HeLa cells grown for 24 h with[3H]-adenosine and compared with ADP-ribosylated histone H1 synthesized from [3H]NAD by isolated HeLa nuclei. Most (ADP-ribose)n-histone H1 conjugates formed in vivo carried single ADP-ribose units, less than one fourth of the total ADP-ribose residues being in the form of oligomeric or polymeric chains. (ADP-ribose)n linked to H1 in vivo was not released by neutral NH2OH to a significant extent. Alkali treatment (pH 10.5) liberated most but not all of the ADP-ribose residues which may indicate the existence of a new type of linkage so far found only in conjugates isolated from intact tissue. No ADP-ribosylated histone H1 complex of higher molecular weight ('H1 dimer') could be detected in intact cells. By contrast, isolated HeLa nuclei formed ADP-ribosylated histone H1 which contained predominantly polymeric ADP-ribose residues. The (ADP-ribose)n residues were linked by NH2OH-sensitive and by NH2OH-resistant, alkali (pH 10.5) labile bonds, the majority of the conjugates appearing in the form of the higher-molecular-weight complex. A comparison with the ADP-ribosylated non-histone proteins indicated that histone H1 formed in vivo carried less than 2.5% of the total protein-bound ADP-ribose residues and less than 1% of the protein-bound ADP-ribose synthesized in vitro.


Subcellular localisation and identification of superoxide dismutase in the leaves of higher plants.

1. The subcellular location of superoxide dismutase in the leaves of spinach and other C3 plants has been investigated. 2. Most activity appeared to be located within chloroplasts. These organelles contain a cyanide-sensitive (copper-zinc) superoxide dismutase, most of which is located in the stroma although some is bound to the thylakoids. 3. Intact chloroplast fractions also contain a cyanide-insensitive (manganese) superoxide dismutase, but this activity is located on the outside of the chloroplasts and may be adsorbed onto them during isolation. 4. Leaf mitochondrial fractions contain only a small percentage of total leaf superoxide dismutase activity, but there is more than can be accounted for by contamination with chloroplasts. 5. Mitochondria contain both a cyanide-sensitive dismutase, apparently located in the intermembrane space, and a cyanide-insensitive activity, apparently located in the matrix. 6. The microsomal fraction contains no superoxide dismutase activity.


Isolation of thiomolybdate compounds from the molybdenum-iron protein of clostridial nitrogenase.

Acid/base treatment of the molybdenum-iron protein of the nitrogenase from Clostridium pasteurianum 25 yields low-molecular-weight compounds of molybdenum, which can be separated from the protein by gel chromatography. Elementary analysis and spectral properties relate these compounds to thiomolybdate anions. It is proposed that in its native state nitrogenase contains a thio complex of molybdenum coupled to iron-sulfur clusters.


Fluorescence of aromatic amino acids in a pyridoxal phosphate enzyme: aspartate aminotransferase.

At pH 8.3, the fluorescence spectrum of apoaspartate aminotransferase is characteristic of buried tryptophans (maximum at 330 nm and width at half-height equal to 51 nm). Its quantum yield is 1.69 times larger than for tryptophan in H2O and the mean decay time is 2.5 ns for the fluorescence emitted at wavelengths higher than 335 nm. Polarization of excitation spectrum (minimum at 305 nm for an emission at 360 nm), suggests an inter-tryptophan energy transfer. Accessibility to a quencher of fluorescence indicates that 34% of the fluorescence can be extinguished by iodide with a quenching constant of 4 M-1; as shown by solvent perturbation spectroscopy, this partial accessibility is related to two tryptophan residues accessible to solvent. At pH 5, the relative quantum yield is slightly lower than at pH 8.3 (1.65). Binding of the pyridoxal-P coenzyme diminishes the fluorescence quantum yield relative to tryptophan to 0.51 at pH 8.3 and 0.595 at pH 5; the decrease is smaller in the presence of pyridoxamine-P. Since the fluorescence of the coenzyme is very weak it is difficult to observe its emission sensitized by tryptophan, nevertheless, since the quenching is larger for pyridoxal-P that absorbs at 360 nm than for reduced pyridoxal-P that absorbs at 330 nm, it is deduced that the energy is transferred preferentially from exposed tryptophans. It is proposed that conformational changes in the vicinity of buried tryptophans are responsible for the remaining quenching. This hypothesis of conformational changes induced by the binding of the coenzyme is in agreement with the observed fluorescence emission of tyrosine. In the apoenzyme the tyrosine quantum yield is zero and the energy is entirely transferred to tryptophan. In the holoenzyme the quantum yield is low and the efficiency of transfer to tryptophan is 0.13 in pyridoxal-P form and 0.7 in pyridoxamine-P form. According to the Förster theory of long-range energy transfer, a change of transfer efficiency can be attributed to a modification either of the mutual orientation of tyrosine and tryptophan residues or of the distance between these residues: both interpretations correspond to a conformational change.


The quaternary structure of bovine alpha-crystallin. Size and charge microheterogeneity: more than 1000 different hybrids?

Cortial alpha-crystallin was size-fractionated by gel filtration on Ultrogel AcA22 and charge-fractionated by anion-exchange chromatography on DE-52 DEAE-cellulose using gradient elution. Electron microscopy demonstrates that both native and reassociated alpha-crystallin are heterogeneous populations of spherical or slightly ellipsoidal molecules with diameters of 13.5--16.0 nm (maximum at 14.0--15.0 nm) for native alpha-crystallin and 8.5--12.5 nm (maximum at 10.0--10.5 nm) for reassociated alpha-crystallin. An enormous charge heterogeneity of native alpha-crystallin was detected, which is shown to arise from variations in the stoichiometry of the 5 main types of subunits. The molar ratio of acidic chains (A2, A1 and A1/2-151) to basic chains (B2 and B1) varies from 70/30--80/20 (averaging about 3/1) and the amount of deamidated chains (A1 and B1) varies from 7--37%. Recombination of the subunits, after dissociation in 6 M urea, leads to a charge heterogeneity of reassociated alpha-crystallin very similar to that of native alpha-crystallin. Therefore, specific formation of pure A or B chain aggregates is not preferred. Instead, random combination of subunits is theoretically shown to be sufficient to describe the observed charge microheterogeneity of both reassociated and native alpha-crystallin. No obvious relationship exists between size and charge heterogeneity. Within these ranges of molecular weight and subunit composition there are more than 1000 different combinations of A2, A1, A1/2-151, B2 and B1 conceivable.


Evidence in rat and mouse liver for temporal control of two forms of cytochrome P-450 inducible by 2,3,7,8-tetrachlorodibenzo-p-dioxin.

In the liver of perinatal rats or mice, the ratio of 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced aryl hydrocarbon hydroxylase to total cytochrome P-450 content decreases, whereas the ratio of 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced acetanilide 4-hydroxylase to total cytochrome P-450 content increases, between 18 or 19 days and 22 days following conception. The ontogenesis of inducible aryl hydrocarbon hydroxylase corresponds well with increases in a 56000-Mr electrophoretic band; we suggest this band represents the cytochrome P1-450 subunit. The later temporal expression of inducible acetanilide 4-hydroxylase closely parallels 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced increases in size of a 54000-Mr electrophoretic band and a 2--3-nm hypsochromic shift in the Soret peak of the total microsomal reduced cytochrome P-450 . CO complex. We suggest this band represents the cytochrome P-448 subunit. Previous work from this laboratory has shown that this developmental difference is separated by several weeks in rabbit liver, as compared with several day's separation shown in this report with rat or mouse liver. The data here therefore provide evidence in the rodent for temporal control of the expression of different structural gene products regulated by the Ah locus.


The LD-carboxypeptidase activity in Gaffkya homari. The target of the action of D-amino acids or glycine on the formation of wall-bound peptidoglycan.

The effects in vitro of D-amino acids or glycine on the formation of wall-bound peptidoglycan were studied with wall membrane enzyme preparations from Gaffkya homari. These amino acids inhibited the incorporation of nascent peptidoglycan into the preformed polymer (e.g. ID50 values for D-alanine, D-leucine, and glycine = 5.6 mmol/l, 1.3 mmol/l, and 11 mmol/l, respectively). The inhibition was accompanied by an incorporation of the inhibitor into position 4 of the peptide subunit Ala1-DGlu2(Lys3-DAla4), where the indices refer to the position of an amino acid residue within the peptide subunit. It is suggested that the reaction is catalyzed by an LD-carboxypeptidase. Therefore, this enzyme has also D-amino acid exchange activity. At inhibitory concentration fewer tripeptide subunits were formed in the nascent peptidoglycan in favour of the formation of tetrapeptide subunits bearing the inhibitor at the C termini. The tripeptide subunits are assumed to be necessary in order that nascent peptidoglycan is utilized as substrate in the transpeptidation reaction. Thus an essential role of the LD-carboxypeptidase is indicated.


Degradation of unsaturated fatty acids. Identification of intermediates in the degradation of cis-4-decenoly-CoA by extracts of beef-liver mitochondria.

1. cis-4-Decenoyl-CoA, an intermediate of linoleic acid catabolism, is degraded by a soluble enzyme fraction of beef liver mitochondria to octanoyl-CoA. cis-2-Octanoly-CoA is not observed among the intermediates of this degradation sequence. 2. The existence of a mitochondrial 4-enoyl-CoA reductase which is distinct from the 2-enoyl-CoA reductase is demonstrated in beef liver. 3. Substrates for the 4-enoyl-CoA reductase are acyl-CoA esters, which possess a 2,4-diene structure rather than those containing an isolated double bond in position 4. 4. The 4-enoyl-CoA reductase is involved in the catabolism of cis-4-decenoyl-CoA. 5. A reaction sequence for the degradation of cis-4-decenoyl-CoA to octanoyl-CoA is proposed which combines the 4-enoyl-CoA reductase with the 'classical' beta-oxidation enzymes.


N-Acetylneuraminic acid: a constituent of the lipopolysaccharide of Salmonella toucra.

The composition of lipopolysaccharide and polysaccharides isolated after acidic or alkaline degradation of lipopolysaccharide of Salmonella toucra has been investigated. The following analytical methods were used in this study: gel-filtration and ion-exchange techniques, paper and gas-liquid chromatography as well as spectrophotometric analysis. The products of the lipopolysaccharide degradation were fractionated on the Sephadex G-25 and Sephadex G-50 columns. Lipopolysaccharide and products of its degradation besides glucosamine, galactose, glucose, heptose(s) and 3-deoxy-D-manno-octulosonate described as 'basal' sugars, also contained N-acetylneuraminic acid and an unidentified amino sugar.


Globin messenger precursor RNA in duck immature red blood cells.

A procedure is described for the chromatographic analysis of RNA under fully denaturing conditions on cross-linked Sepharose. Chromatography of DNA . RNA hybrids, poly(C) . poly(G) hybrids and complexes of poly(C) . hnRNA on Sepharose CL in pure formamide at 46 degrees C leads to denaturation and strand separation of the hybrid structures. Using this procedure, nuclear RNA from duck immature red blood cells was resolved according to molecular size and assayed for the presence of globin mRNA sequences by hybridization with complementary DNA. Two size classes of putative globin mRNA precursor molecules were detected at an elution position corresponding to 14--18 S and 23--28 S. As judged from chromatographic analysis on poly(U)-Sepharose, about 70% of the 14--18-S globin precursor RNA is polyadenylated while only 11% of the putative 23--28-S precursor RNA has a poly(A) tract. Inhibition of transcription by actinomycin D and pulse-chase experiments indicate a half-life of less than 7.5 min for these precursor RNA species.


Fractionation of brain microtubule-associated proteins. Isolation of two different proteins which stimulate tubulin polymerization in vitro.

Two different tubulin-assembly-promoting proteins were isolated from porcine brain microtubule protein. Following a heat step performed on microtubule protein, the thermal-stable proteins were fractionated by chromatography on phosphocellulose and Sepharose 4B. Two highly purified associated proteins were obtained. One resembles the previously described MAP2 protein (polypeptide molecular weight approximately 300,000), the other a mixture of four or five polypeptides previously described as tau protein (molecular weights between 55,000 and 70,000). Both proteins stimulate the polymerization of pure brain tubulin into microtubules with comparable activity. The resulting microtubules were characterized by electron microscopical analysis. Microtubules polymerized in the presence of MAP2 protein show typical side projections, which are conspicuously absent in microtubules assembled in the presence of tau protein. The latter microtubules show smooth surfaces. Some biochemical similarities and differences between the two different microtubule-associated proteins are discussed.


Effect of phospholipid depletion by phospholipases on the properties and formation of the multiple monoamine oxidase forms in the rat liver.

The effect of phospholipid depletion by phospholipases on the properties and formation of monoamine oxidase A and B been investigated. The enzyme was solubilized, partially purified, treated with phospholipases and subjected to get filtration to reduce the amount of enzyme-associated phospholipids. Phospholipase A treatment of the purified monoamine oxidase fraction had no effect on the deprenil inhibition pattern or the observed transition temperatures in the Arrhenius plots. However, the rate of enzyme inactivation by heat and trypsin were greatly increased but differences in rates of inactivation of monoamine oxidase A and B were still observed. Phospholipase C treatment of the enzyme fraction had no effect on the deprenil inhibition pattern, Arrhenius plots, heat stability or trypsin digestibility. The inhibition pattern of membrane-bound monoamine oxidase and the phospholipase-treated fractions by propargylamine showed a reduced substrate specificity compared to deprenil suggesting a hydrophobic region in the enzyme is a factor involved in the structural differences of monoamine oxidase A and B.


Type-I trimer and type-I collagen in neutral-salt-soluble lathyritic-rat dentine.

Triple-helical collagen molecules have been obtained from EDTA-demineralized lathyritic rat incisors by neutral buffer extraction. Component alpha chains, isolated by sequential ion-exchange and gel-filtration chromatography, were shown to be alpha1 I and alpha2 chains by cyanogen bromide peptide analysis. The alpha1 I:alpha2 chain ratio was approximately 3:1, which is greater than expected for type I collagen. The excess of alpha1 I chains over that required for type I collagen was due to the presence of type I trimer molecules. Fractional salt precipitation separated type I collagen from type I trimer. It is not known at present if type I trimer synthesis also occurs in normal rat tissues.


Chemical and spectral properties of putidamonooxin, the iron-containing and acid-labile-sulfur-containing monooxygenase of a 4-methoxybenzoate O-demethylase from Pseudomonas putida.

Gel chromatography indicates that putidamonooxin has a molecular weight of about 126,000. On the other hand, the amino acid composition and the iron-to-protein ratio point to a minimal molecular weight of 33,000 and 31,000 respectively. On sodium dodecylsulfate/polyacrylamide gel electrophoresis the enzyme migrated as a homogeneous band corresponding to a molecular weight of about 40,000. The number of spots found in the tryptic peptide map of the carboxymethylated and digested enzyme indicates that putidamonooxin is composed of three or four identical subunits. After covalent cross-linking of the subunits with dimethyl suberimidate and subsequent dodecylsulfate electrophoresis the main bands were in the molecular weight range of 40,000, 87,000 and 124,000. These findings lead us to propose that putidamonooxin is either a trimer or tetramer. The amino acid composition of putidamonooxin and related data calculated from this are given. The isoelectric point was shown by isoelectric focusing to be a pH 4.7. Low-temperature optical spectra of the reduced and oxidized enzyme as well as of three different putidamonooxin.substrate complexes are given together with those recorded at 10 degrees C. Enzyme.substrate binding spectra are observed with the oxidized putidamonooxin but not with the reduced enzyme. For the oxidized putidamonooxin a molar absorption coefficient at 455nm of 14.7mM-1  cm-1 was determined. Ks values of putidamonooxin towards different substrates and substrate analogues (i.e. tight couplers, partial uncouplers and uncouplers) are presented and possible reasons for the difference between the Ks values here  obtained and the previously reported Km values are discussed.


Accessibility of ribosomal proteins to lactoperoxidase-catalyzed iodination following phosphorylation and during subunit interaction.

Lactoperoxidase-catalyzed iodination was employed as a probe to monitor conformational change in 40-S ribosomal subunits from rat liver. Using this probe, it was observed that phosphorylation of protein S6 resulted in no detectable change in the iodination pattern of 40-S subunit proteins. These results suggest that the conformation of the small subunit remains unaltered following phosphorylation. On the other hand, the differences noted in the iodination pattern between 40-S ribosomal proteins derived from isolated subunits and those from 80-S monosomes, suggest that the 40-S subunit undergoes a conformational change during association with the 60-S subunit. Following 40-S and 60-S subunit association, proteins S2, S3, S5, S6, S8, S10 and S14 became less accessible to iodination. It is suggested that these proteins may be located at the interface between the 40-S and 60-S subunits.


The poly(glycosyl) chains of glycoproteins. Characterisation of a novel type of glycoprotein saccharides from human erythrocyte membrane.

Glycopeptides with complex carbohydrate structure were isolated from delipidated human erythrocyte membranes after digestion with pronase. The poly(glycosyl)peptides isolated (apparent molecular weight 4000--13000) are suggested to contain 20--70 sugar residues in an alkali-stable saccharide chain linked through N-acetylglucosamine to asparagine. The main sugar components are galactose and N-acetylglucosamine, which together account for 80% of total sugars. That the compounds isolated are glycopeptides and not glycolipids is concluded from the following findings: only trace amounts of glucose and fatty acids were present, and no long-chain (sphingosine) bases could be detected; on the other hand, the amounts of mannose and amino acids found are compatible with an N-glycosidic poly(glycosyl)peptide structure. The structure of the poly(glycosyl)peptides was studied using methylation analysis, exoglycosidase treatments, acid hydrolysis of the native as well as the N-deacetylated glycopeptides, and chromium trioxide oxidation. The studies indicate that the poly(glycosyl)peptides contain a repeating-3)galactosyl(beta1-4)N-acetylglucosaminyl(beta1-structure with branch points at the C-6 of the galactose residues. The saccharide chains are terminated in N-acetylglucosaminyl, galactosyl, N-acetylneuraminyl(alpha2-3 and 6)galactosyl and fucosyl(alpha1-2)galactosyl residues, and they also contain blood group A and B determinants.


Structure and replication of echovirus type 12. 1. Analysis of the polypeptides and RNA of echovirus 12 particles.

The propagation of echovirus 12 in green monkey kidney (GMK) cells, a continuous cell line, is described. Virions and empty capsids are purified to homogeneity by CsCl density and by velocity centrifugation. The protein composition of the particles as compared to poliovirus 2 particles is analyzed by dodecyl sulfate/polyacrylamide gel electrophoresis. Infectious virions were found to be composed of four different polypeptide chains of molecular weights 33,000, 31,000, 24,000 and 7,000. Some additional polypeptide bands at low concentrations are also visible. The empty capsids lack the 31,000-Mr and 7,000-Mr components and contain instead a polypeptide of the molecular weight 46,000. The molecular weights of the structural polypeptides are the same regardless of whether the virus has been synthesized in primary African green monkey kidney cells or in the continuous GMK cell line. The sedimentation behavior of echovirus 12 RNA is shown to be similar to that of poliovirus 2 RNA.


Structure and replication of echovirus type 12. 2. Viral polypeptides synthesized in the infected cell.

A technique has been devised which allows us to label predominantly echovirus-12-specific proteins: upon infection in the presence of D-(--)-2-(alpha-hydroxybenzyl)benzimidazole plus actinomycin D the shut-off of host-cell protein synthesis takes place as in infected, untreated cells, but the bulk of viral protein synthesis is inhibited. Upon removal of 2-(alpha-hydroxybenzyl)benzimidazole a peak of viral protein synthesis is visible 3 h later. The time course of appearance of viral proteins is followed by dodecyl sulfate/polyacrylamide gel electrophoresis of the proteins which had been pulse-labeled at different times post-infection. The protein patterns induced in the infected cells by echovirus 12 and poliovirus 2 are compared; though they are different, some analogies are observed. The molecular weights of the polypeptides are determined. In the presence of amino acid analogs cleavage of viral proteins is impaired. A group of large proteins up to Mr 220,000 is detectable in the infected cell which ordinarily is not observed. The 220,000-Mr protein may represent the translation product of the total viral RNA. The hierarchy of the virus-specific proteins originating from post-translational cleavage is discussed.


5'-Terminal 7-methylguanosine and mRNA function. The effect of enzymatic decapping and of cap analogs on translation of tobacco-mosaic-virus RNA and globin mRNA in vitro.

1. Decapped tobacco mosaic virus (TMV) RNA and rabbit globin mRNA were prepared by enzymic treatment of RNAs with nucleotide pyrophosphatase purified from potato. The extent of removal of 5'-terminal 7-methylguanosine 5'-monophosphate (m7GMP) from TMV RNA was at least 97% as estimated by labeling of the 5' termini in vitro with S-adenosyl[methyl-3H]methionine catalysed by vaccinia virus methyltransferases. 2. The effect of enzymic decapping was compared with the effect of cap analogs on mRNAs translation in a nuclease-treated rabbit reticulocyte lysate and in a wheat germ extract. When translation was studied at low K+ concentration, little or no dependence on 5'-terminal 7-methylguanosine was found with either cell-free system. The importance of the 5'-terminal cap for the efficient translation of TMV RNA and globin mRNA increased as the concentration of K+ in a protein-synthesis system was raised. In a reticulocyte lysate analogs and enzymic decapping had a similar effect on translation. In a wheat germ extract, mRNA decapping resulted in a more pronounced decrease of mRNA activity, presumably due to the increased susceptibility of decapped mRNAs to the nucleases present in this protein synthesis system. 3. The requirement for a 5'-terminal cap was similar for the synthesis of 130,000-Mr and 165,000-Mr polypeptides coded by TMV RNA. This indicates that both proteins may be initiated at the common site close to the 5' terminus.


Spontaneous and provoked coronary artery spasm: are they the same?

A 44-yr-old man suffering fro exertional, emotional and spontaneous angina underwent coronary arteriography. During the examination he had a spontaneous attack of angina with ST elevation in the anterior leads. Injection of a contrast medium in the left coronary artery during pain showed marked spasm with anterior descending artery occlusion. The spasm was quickly relieved by nitroglycerin. Intravenous administration of 0.4 mg of ergonovine maleate reproduced the anginal episode with pain, ST elevation in the anterior leads and coronarographic patterns of a spasm occluding the anterior descending artery at the same level. After nitroglycerin, the pain disappeared and the electrocardiographic and coronarographic findings returned to basal conditions.


Chronic juvenile AV nodal dysfunction associated with mitral valve prolapse.

The prevalence of atrioventricular (AV) conduction disturbances amongst patients with mitral valve prolapse is higher than may be expected by chance, thus implying the existence of a true association. The main clinical and electrophysiologic findings in 4 patients with mitral valve prolapse showing chronic AV conduction disturbances are presented. Supra-His localization, mild and variable degree of impairment, regression upon Atropine administration, apparent absence of progression, are common features of these disturbances. The most likely mechanisms considered are an AV node developmental abnormality or an AV nodal artery running in contact with the border of the mitral annulus and thus impaired by the abnormal dynamics of the mitral valve.


Myoglobinemia after myocardial infarction; influence of renal function.

Using a solid-phase radioimmunoassay for detection of serum myoglobin, the pattern of myoglobinemia was investigated in patients with acute myocardial infarction. All patients with acute infarcts had a marked rise in serum myoglobin concentration. Peak serum myoglobin concentration was found on an average 9 h after the initial onset of chest pain. Late onset of myoglobin peaks without signs of reinfarction as well as sustained abnormal myoglobinemia, in the majority of patients, could be explained by impaired renal function. The peak serum level of myoglobin correlated (r = 0.92) to the peak level of ASAT supporting the idea that the detection of myoglobin in serum may be a useful diagnostic aid in the qualitative diagnosis of myocardial infarction.


Partial atrial standstill in sick sinus syndrome; intraatrial and AV nodal block with short PR interval.

Standstill and inexcitability (quiescence) of the high right atrium could be demonstrated in a patient with sinus node dysfunction and bradycardia--tachycardia syndrome. The onset of P wave in surface electrocardiogram did not represent the beginning of atrial excitation but followed 130 msec the high right atrial and 50 msec the low right atrial deflection, leading thereby to a short PR interval which gave misinformation on the atrioventricular conduction. A pacemaker implant with right ventricular stimulation freed the patient of his previous complaints. 4 wk after the implantation the demand unit was inhibited for 5 h by external stimulation. Continuous ECG monitoring, esophageal ECG recording and fluoroscopic study could not reveal any atrial activity. The conditions for atrial pacemaker implantation are discussed.


Quantitative assessment of myocardial infarction prognosis to 1 and 6 mth--from clinical data.

Survival of 312 patients with acute myocardial infarction was studied from data collected during the first 48 h in the coronary care unit. Only patients with recent onset of symptoms (48 h), with a 48-h survival, and with evidence of myocardial infarction, were selected. Mortality rate at 1 mth was 15.3% and 24.6% at 6. The following factors were significant for poor survival: increasing age, female sex, diabetes, previous angina, low blood pressure on admission and at the 48th h low average value and the lowest observed value of blood pressure, clinical and radiological left ventricular failure, high level of LDH, increased urea and leukocytosis. Among ECG data, the presence of signs related to extent of infarction, anterior as compared to inferior location, antero-lateral as compared to anterior, QRS frontal axis deviation, absence of sinus rhythm, sinus tachycardia, tachyarrhythmias with wide QRS complex, right bundle branch block, 3rd-degree AV block with wide QRS complex, was associated with significantly worse survival than the absence of these signs. A multivariate analysis of the 42 most significant data, assuming linear regression, was used to establish a discriminant prognostic index. Using this index, survival was predicted correctly in 90.2% of patients at 1 mth and 85.7% at 6 mth. Thus prognosis can be established in nonclear-cut groups of patients with myocardial infarction (severe and benign forms being excluded by criteria) from simple clinical data.


Electrocardiographic and hemodynamic effects of tocainide (W-36095) in man.

Tocainide is a new antiarrhythmic drug with a chemical structure related to that of lidocaine. In the present study, healthy volunteers were investigated after infusion of tocainide 450 mg over 45 min. In nine subjects His bundle electrograms, sinus recovery time and ventricular effective refractory periods were recorded. No major changes were seen. In eight cases the hemodynamic effects at rest and during exercise were studied. No significant circulatory effects were observed. No clinically important side-effects were noted.


Metabolism of procainamide in patients with chronic heart failure, chronic respiratory failure and chronic renal failure.

Fractional hydrolysis and acetylation of procainamide, acetylation of procainamide-derived p-aminobenzoic acid and plasma hydrolysis of procaine were studied in 20 patients with chronic heart failure (CHF), 20 patients with chronic respiratory insufficiency (CRI) and 20 patients with chronic renal failure (RF). The results were compared with those obtained in a group of 20 normal volunteers. Hydrolysis of procainamide and procaine were reduced in patients with CHF and CRI, but not in patients with RF. Moreover, more marked decreases in procainamide and procaine hydrolysis were seen in subgroups with secondary hepatic dysfunction. The diminution of hydrolysis of procainamide was not paralleled by changes in acetylation of procainamide or p-aminobenzoic acid. It is concluded that in patients with hepatic involvement secondary to advanced CHF or CRI, hepatic and plasmatic hydrolysis activity is decreased to a degree equivalent to primary liver failure.


Patterns of drug prescribing for children in hospital.

The drugs prescribed for children in Tayside hospitals in 1974 and 1975 were surveyed using the computer files of over 4000 children in each year. The results were compared with similar data on adult patients. Although similar proportions of both age groups received drugs, less than 3 drugs were prescribed for the great majority of the children (mean 2.5) compared with twice that number for adults. Seven classes of drugs accounted for almost four-fifths of the drugs prescribed for children but the same classes formed two-fifths only of the total drug use in adults. There was significantly greater use of antihistamine/sedative, anticonvulsant and decongestant/mucolytic drugs in children than in adults while the reverse was true for diuretics, KCL, cardio active agents, sedatives/hypnotics, and tranquillisers. Antimicrobial drugs accounted for approximately one-third of the total drugs used in children and one half of all patients received at least one drug from this class. Penicillin preparations alone accounted for 65.1 per cent of all antimicrobial drug use. The percentage of children given ampicillin fell by almost half from 1974 to 1975 with a corresponding increase in the proportion receiving amoxycillin.


Brain concentrations of carbamazepine and carbamazepine-10,11-epoxide in epileptic patients.

Carbamazepine (CBZ) and carbamazepine-10,11-epoxide (CBZ-Epoxide) in the temporal lobe were measured in five epileptic patients undergoing unilateral temporal lobectomy. The patients had been under CBZ treatment from 6 months to 6 years and all were in steady state at the time of operation. The brain tissue concentration of CBZ in all patients was higher than the plasma concentration; the brain/plasma ratio ranged from 1.4--1.6. Brain/plasma ratios of CBZ-Epoxide ranged from 0.6--1.5. The ratio for CBZ was similar in patients treated with CBZ alone or in combination with other anticonvulsants, but for the CBZ-Epoxide a higher ratio was found in patients on combined treatment. The results may mean that other antiepileptic drugs, too, can influence the brain concentration of an active metabolite, which could have a bearing on the enhanced therapeutic effect often seen on combining CBZ treatment with other antiepileptic drugs.


Effect of topical application of dexamethasone on Propionibacteria in the pilosebaceous duct.

A preparation of dexamethasone 0.02% in Eutanol G (n octyldodecanol) was applied once daily for three weeks, to the right side of the forehead of 25 male healthy test subjects. Eutanol G without dexamethasone was applied in the same way to the left side of the forehead. Before and at the end of the treatment period bacteria were removed from the pilo-sebaceous ducts by the method of Holland et al. [8]. Bacteria that grew under anaerobic conditions were evaluated quantitatively. Dexamethasone induced a significant increase in P. acnes, in all Propionibacteria and in the total bacterial count. The importance of these findings is discussed in relation to the development of steroid acne.


Pharmacokinetics of sulfadiazine and trimethoprim in man.

Sulfadiazine (SDZ) 800 mg and trimethoprim (TMP) 160 mg were given orally to 10 normal subjects and the concentration of SDZ and TMP in serum and urine was followed for 24 h. Both drugs showed a significant negative correlation between individual "peak" concentrations in serum and the body weight of the subject. Twelve hours after dosing the serum concentration was 12 to 25 microgram/ml for SDZ and 0.3 to 1.1 microgram/ml for TMP. Individual concentration ratios between SDZ  and TMP in serum were 4.8 (1 h)--145 (24 h), and in the urine the ratio was close to 6 throughout the 24 h collection period. The range of urinary concentrations was from 65 to 400 microgram/ml for SDZ and from 13.8 to 93.4 microgram/ml for TMP. The fraction (formula: see text) was 21% during the 0--8 h period, 33% during the 8--15 h period and 41% during the 15--24 period. The average "t1/2" was 15.2 +/- 7.4 h for SDZ and 7.4 +/- 1.9 h for TMP. Individual subjects showed a significant correlation between the serum clearance of TMP and SDZ (p less than 0.01) and also between the renal clearance of the two drugs (p less than 0.05). The serum clearance was significantly correlated with the renal clearance for TMP but not for SDZ. For SDZ Vd was significantly negatively correlated with the elimination constant; for TMP no such correlation was found. The serum clearance of SDZ was significantly correlated with the percentage of SDZ which was excreted as the (presumably) acetylated compound. The renal clearance of SDZ was independent of the serum concentration of SDZ. There was a highly significant negative correlation between the renal clearance and serum concentration of TMP, as well as for "acetylated SDZ". The renal clearance of "acetylated SDZ" averaged more than six times that of unconjugated SDZ. With increased urine flow the renal clearances of TMP and SDZ were significantly increased.


Preliminary studies of the kinetics of citalopram in man.

The plasma concentrations of citalopram, a potent serotonin reuptake inhibitor, and its demethylated metabolite have been determined by a specific fluorescence coupling technique during single dose experiments in volunteers and in clinical tests. Citalopram was found to have linear kinetics within the dose range investigated, which were characterized by fairly rapid absorption and slow elimination (biological half-life 1--21/2 days). Steady state levels in the range 120--340 nM (i.e. slightly above those associated with pharmacodynamic activity in animals) were attained within a week. A drug/metabolite ratio of 2--3 was recorded.


Clinical and pharmacological investigations of the new saluretic azosemid.

Ple 1053 (Azosemid) is a diuretic which resembles furosemide chemically and in its mode of action. When administered intravenously, Ple 1053 was approximately 5 times more potent on a weight basis than furosemide, its dose-response relationship was closer and the slope was steeper. After oral administration Ple 1053 and furosemide were approximately equal in potency. However, the effect of Azosemid in healthy subjects was relatively prolonged and abrupt peaks did not occur.


Comparison of the duration of action of pindolol and slow release oxprenolol in healthy volunteers.

The duration and extent of the reduction of exercise-induced tachycardia, as a measure of cardiac beta-adrenoceptor blockade were studied in 12 healthy volunteers after administration of single oral doses of pindolol 15 mg (Visken) or 160 mg slow release oxprenolol (Slow-Trasicor). The mean maximum effect was reached after 1.6 +/- 0.3 h with pindolol and after 2.5 +/- 0.2 h with slow release oxprenolol. The reduction in heart rate during exercise was virtually identical after both drugs, amounting to -36.1 +/- 1.7 beats/min after pindolol and -36.3 +/- 1.6 beats/min after slow release oxprenolol. The duration of action of pindolol, however, was clearly longer than that of slow release oxprenolol: after 24 h pindolol still exerted 39.6 +/- 5.6% of its maximum activity, as against 22.1 +/- 3.6% for slow release oxprenolol.


Comparison of serum phenytoin levels in epileptic patients who swallowed their phenytoin tablets with or without previous chewing.

This cross-over study was conducted to compare serum phenytoin levels after chronic ingestion of phenytoin tablets with or without previous chewing. The phenytoin therapy was administered as 50 mg chewable Infatabs tablets in a single morning dose of 200 mg. There was no significant difference between the two modes of ingestion as regards serum phenytoin levels measured at various times after ingestion of the phenytoin tablets. Moreover, the area under the curve did not differ significantly during the 24 h interval. Minor changes between two Dilantin formulations, however, could influence drug availability.


Pharmacokinetics of perhexiline maleate in anginal patients with and without peripheral neuropathy.

Perhexiline maleate (Pexid) which has been in general use in France with good results for the treatment of angina pectoris since 1973, may be associated with severe side effects including peripheral neuropathy. The present study is a comparison of the pharmacokinetics of perhexiline maleate in anginal patients with and without signs of peripheral neuropathy. Compared to the latter, those with neuropathy had higher plasma levels of perhexiline, slower hepatic metabolism and a longer plasma half-life. Thus, peripheral neuropathy associated with perhexiline maleate treatment appears to be a direct toxic effect due to accumulation of the drug. The accumulation might result either from a decreased volume of distribution secondary to a loss of body weight, possibly drug-induced, or to slow hepatic metabolism of perhexiline of genetic origin or due to hepatic disease, possibly drug-induced. The neuropathy is rarely an isolated event, as it is often associated with one or more adverse effects of perhexiline.


An alternative method of assessing changes in salivary flow: comparison of the effects of clonidine and tiamenidine (HOE 440).

An established method for collecting uncontaminated parotid saliva has been applied to assessment of salivary flow rate. Following single doses of 0.3 mg clonidine and 1.0 mg tiamenidine (HOE 440) changes in blood pressure, heart rate, sedation (assessed by a self-rating scale) and salivary flow were followed in nine normal subjects. Both drugs produced a fall in systolic and diastolic blood pressure, sedation, depression of salivary flow and a lowering of heart rate. These changes were maximal between 2 and 6 h and were more marked after clonidine than after tiamenidine. As tiamenidine 1.0 mg did not produce a hypotensive effect equivalent to clonidine 0.3 mg direct comparison of side-effects attributable to these agents proved difficult. The evidence suggests, however, that tiamenidine would cause sedation and reduction in salivary flow comparable to clonidine if given in an equivalent hypotensive dose.


Dose tolerance and pharmacokinetic studies of L (+) pseudoephedrine capsules in man.

Dose tolerance and pharmacokinetic studies of pseudoephedrine sustained action capsules were performed in thirty-three adult male subjects who received either 120 mg or 150 mg capsules every twelve hours for seven consecutive days in a double-blind parallel design study. Although only one subject in the 150 mg group was discontinued prematurely from this study, a large number of side effects typical of CNS stimulation were seen. A placebo effect might account for a portion of these complaints, however symptoms evaluated as being due to drug were significantly more severe and persistent in the 150 mg group. Pulse rates showed a persistent and significant increase while systolic and diastolic blood pressure fell from the baseline values in both groups. A pharmacokinetic analysis of the pseudoephedrine plasma concentration-time data provided estimates of half-life and the volume of distribution/availability ratio. The values obtained were in good agreement with values reported by others. Half-life was not influenced by urine pH probably as a result of the narrow range of urine pHs observed in the subjects. Calculations of relative bioavailability suggest that the 120 mg capsule formulation has a 30% greater bioavailability compared to the 150 mg capsule.


The pharmacokinetics of slow-release procainamide.

Procainamide was given to 20 patients with normal renal function as an i.v. bolus of 500 mg followed by 1.0 or 1.5 g eight-hourly by mouth in the form of a slow release preparation (Durules). 97.6 +/- 27.1 (SD)% of the oral procainamide was absorbed, the absorption half life being 1.54 h. The elimination half life following the oral formulation was 6.0 +/- 0.8 h, compared to a mean of 3.4 +/- 0.4 h following i.v. administration. Elimination half life following i.v. administration was slightly related to acetylator status, being 2.75 +/- 0.9 h in fast acetylators, and 4.4 +/- 2.4 h in slow acetylators. This dependence on acetylator status was not seen in half life following oral administration. Total body clearance, steady state plasma procainamide and N-acetylprocainamide were not significantly dependent on acetylator status, although a few patients who are slow acetylators had unexpectedly low clearance and high steady state procainamide concentrations when given the higher dose.


Clinical pharmacology in normal volunteers of praziquantel, a new drug against schistosomes and cestodes. An example of a complex study covering both tolerance and pharmacokinetics.

The tolerance of Praziquantel (2-cyclohexylcarbonyl-1, 3, 4, 6, 7, 11b-hexahydro-2H-pyrazino-[2, 1-a]isoquinoline-4-one) in oral doses of 1 X 20 mg/kg, 1 X 50 mg/kg, 3 X 10 mg/kg and 3 X 25 mg/kg body weight (tau = 4 h) was tested in a complex study involving 36 healthy volunteers. In addition to the usual assessment of clinical chemistry, haematology, coagulation physiology, urinalysis, clinico-physiological examination including EEG, and medical examination, clinico-psychological parameters were also recorded and special neurological investigations were performed. No clinically relevant changes were found in any of the laboratory parameters, nor in the medical-neurological or clinico-physiological examinations. Based on a few clinico-psychological parameters and subjective comments, the largest daily dose tested (3 X 25 mg/kg = 75 mg/kg) produced a slight, transient disturbance in general well-being, which was barely detectable on objective clinical examination. The pharmacokinetic behaviour was dominated by rapid metabolism and pronounced first-pass metabolism of praziquantel, which greatly limits the value of results obtained by GC analysis of unchanged drug in serum. The peak concentration in serum was reached after 1--2 h, and the elimination half-life for the period 2--8 h was 1--1.5 h.


Activity and duration of action of pindolol and alprenolol compared in healthy volunteers.

An improvement in the prognosis of myocardial infarction has been reported after long term treatment with alprenolol 200 mg twice daily. Therefore, an experiment was carried out to find the dose of pindolol given once daily which would show cardiac beta-adrenoceptor blockade at least equipotent to that obtained during treatment with alprenolol 200 mg twice daily. Cardiac beta-adrenoceptor blocking activity and its time course during treatment with pindolol (15 mg and 20 mg given once daily) and alprenolol (200 mg given 12-hourly) for three days were compared in 6 healthy volunteers. The reduction in exercise-induced tachycardia as a measure of cariac beta-adrenoceptor blockade was significantly greater after pindolol 15 mg and 20 mg than after alprenolol 200 mg. On the morning of the fourth day, i.e. 24 h after the last dose of pindolol and only 12 h after the last dose of alprenolol, the effects of pindolol at both dose levels were slightly greater than those of alprenolol. This difference was not statistically significant. It can be concluded that pindolol 15 mg once daily produces a cardiac beta-adrenoceptor blockade at least equipotent to that of alprenolol 200 mg given 12-hourly.


Comparative study of the vasoconstrictor activity of halopredone acetate in a modified McKenzie test.

The vasoconstrictor activity of four steroids, administered in solution and in the commercially available form, were compared in healthy volunteer subjects. Evaluation was based on conventional visual observations and photometric measurement of reflectance. Statistical analysis showed that halopredone acetate had less vasoconstrictor action on healthy skin than fluocinolone acetonide, beta-methasone valerate and hydrocortisone acetate. The halopredone acetate results were identical to those of th excipient, although it was found that halopredone acetate cream (Topicon) had a marked anti-inflammatory effect in animals and on human dermatoses. The validity of the McKenzie test, as an unequivocal screening procedure for the potency of topical steroids is discussed, and the accuracy and precision of photometric evaluation is emphasized.


Effect of indoramin on finger blood flow in vasospastic patients.

The effect of indoramin on blood pressure, heart rate and finger blood flow was investigated in eleven patients with essential acrocyanosis. Indoramin 50 mg t.i.d. and placebo were administered for 6 weeks, in random order in a double blind, cross-over trial. In 8 of the 11 patients, finger blood flow, measured by venous occlusion plethysmography was higher and resistance was lower with indoramin. There was no significant change in blood pressure or heart rate. Thus, indoramin may be useful when a decrease in alpha-adrenoreceptor tone in the fingers is desirable.


Binding of drugs to human muscle.

Binding of 22 drugs to human muscle tissue has been determined by ultrafiltration. All drugs tested were bound, the bound fraction ranging from 13% (aminophenazone) to greater than 98% (desipramine). Both linear and nonlinear binding was observed. For chemically related substances, binding to muscle tissue correlated with plasma binding and lipid solubility. There were significant differences in binding to muscle from different individuals. With respect to pharmacokinetics of drugs, it is suggested that binding to muscle tissue may be at least as important as plasma binding.


The comparative bioavailability of Lanoxin tablets and Lanoxicaps with and without sorbitol.

(1) The mean cumulative urinary digoxin excretion over 8 days was compared in 8 healthy volunteers after single doses of digoxin administered as 3 Lanoxin tablets of 0.25 mg, 3 digoxin tablets of 0.2 mg, 12 Lanoxicaps without sorbitol of 0.05 mg, 6 Lanoxicaps without sorbitol of 0.1 mg digoxin, 3 Lanoxicaps without sorbitol of 0.2 mg and 3 Lanoxicaps with sorbitol of 0.2 mg. (2) There was no significant difference between the 8 day cumulative urinary excretion for any of the Lanoxicaps treatments. (3) Cumulative urinary excretion after 3 digoxin tablets of 0.2 mg was significantly (P less than 0.05) lower than after all other treatments. (4) Cumulative urinary excretion after 3 Lanoxin tablets of 0.25 mg was not significantly different from that after any of the Lanoxicaps treatments except 0.1 mg Lanoxicaps without sorbitol, it was significantly (P less than 0.05) lower after the latter. (5) Mean urinary excretion of digoxin was 60% of ingested dose for all Lanoxicaps treatments and was significantly (P less than 0.05) higher than the mean value of 50% for both tablet treatments. (6) Enhanced absorption of digoxin from Lanoxicaps was confirmed and shown to be unrelated to the sorbitol content of the capsule shell.


Pharmacokinetics of furosemide in gestosis of pregnancy.

Furosemid 50 mg was administered orally and intravenously to twelve gestotic women for brief periods as a part of a randomized, multicentre clinical trial comparing the efficacy of bed rest and pharmacological treatment. The pharmacokinetic profile was investigated using a gas-liquid chromatographic technique. The plasma half-life after oral and intravenous administration was 115 +/- 37.1 and 71.8 +/- 26.3 min and plasma clearance was 153 +/- 48 and 152 +/- 23 ml/min, respectively (mean +/- SD). Comparative data from healthy pregnant women cannot be obtained for ethical reasons. The results show that gestosis has only a marginal if any effect on the kinetics of furosemide in comparison with published kinetic parameters in healthy volunteers, and patients with renal failure. The new-born babies where checked for side effects according to a protocol in use in a larger regional surveillance programme. No clinical side-effects were attributable to furosemide, but the small size of the group does not permit any definitive conclusions about this aspect.


Effects of hypothyroidism on the response of the rat colon to morphine.

Isolated terminal colon strips obtained from rats, made hypothyroid by methimazole treatment, were almost completely insensitive to the contractile effects of morphine as compared to strips from control animals. This low morphine sensitivity was accompanied by a significant (40%) reduction in the tissue sulfatide content. Although colon strips from hypothyroid rats showed a reduction of the contractile effects of acetylcholine, the decrease was considerably less than that noted for morphine. The addition of 6.6 X 10(-5) M tri-iodothyronine to colons from hypothyroid rats largely restored the tissue sensitivity to morphine. These results suggest that sulfatides could be linked to the in vitro effects of morphine in the colon.


Carbachol-induced sensitivity changes in skeletal muscle and their mechanism of action.

Pretreatment of carbachol (in vitro), in various doses (5.5 pM to 550 nM), produced a significant decrease in the sensitivity of the frog rectus abdominis muscle to acetylcholine (ACh), in a dose-dependent manner. This action was observed with a 60 min incubation period. Contractions induced by potassium chloride (KCl) were unaffected by carbachol. Physostigmine (10 micrometer) potentiated the decrease in sensitivity induced by carbachol, whereas human plasma antagonised it. Low calcium (0.27 mM) in the medium and hexamethonium (300 micrometer) antagonised the sensitivity decrease induced by carbachol. These results suggest that carbachol decreases the sensitivity to ACh by releasing ACh from the presynaptic nerve terminals. The results further suggest that carbachol may release ACh by depolarising the presynaptic nicotinic receptors.


Significance of dopamine metabolites in the evaluation of drugs acting on dopaminergic neurons.

The effect of various drugs was studied on 3-methoxytyramine (3-MT) concentrations in rat striatum. The drugs were chosen for their ability to interfere with the dopaminergic system at different levels. Dopamine (DA) acidic metabolites, i.e. homovanillic acid (HVA) and 3,4-dihydroxyphenylacetic acid (DOPAC), were also measured. Changes of 3-MT, unlike those of DOPAC and HVA, seem to reflect the functional activity of dopaminergic neurons. In fact drugs believed to increase or decrease DA content in the synaptic cleft produce predictable changes of striatal 3-MT. Thus cocaine, nomifensine and d-amphetamine increase 3-MT concentrations while gamma-butyrolactone, alpha-methyltyrosine and apomorphine decrease it.


Inhibition of dopamine-stimulated adenylate cyclase activity by phenoxybenzamine.

Phenoxybenzamine at a concentration of 2 X 10(-6 M) produced half-maximal inhibition of dopamine-stimulated adenylate cyclase activity in homogenates of rat striatum. Inhibition was sharply dependent on time and temperature of preincubation with the inhibitor. When included in the preincubation medium, dopamine was nearly 8 times more effective than norepinephrine at protecting against this inhibition, whereas neither isoproterenol nor methoxamine appeared to protect at all. These results suggest a direct, and possibly irreversible, interaction of phenoxybenzamine with the dopamine-binding component of the adenylate cyclase.


Regional and subcellular distribution of myocardial muscarinic cholinergic receptors.

Regional and subcellular distributions of muscarinic cholinergic receptors were investigated in the myocardium of commonly used laboratory animals. The density of receptor sites (expressed in terms of either pmol/g protein or pmol/g tissue), amongst the regions examined, was found much higher in right and left atrium in the case of rat and rabbit whereas for the guinea pig and dog, the distribution was diffuse. However, irrespective of the species and/or region studies, the microsomal fraction, amongst the subcellular fractions, showed the highest enrichment or receptors.


Influence of a cholinergic agent, oxotremorine, on sympathetic reflexes.

Administration of cholinergic substances by various routes has been reported to produce marked cardiovascular effects. The present study examined the influence of a muscarinic agonist, oxotremorine, on aspects of sympathetic function. The compound reduced blood pressure and spontaneous sympathetic outflow in anesthetized cats after blockade of peripheral muscarinic receptors with methylatropine. Effects on potentials evoked in the splanchnic nerve by stimulation of an intercostal nerve, i.e., the somatosympathetic reflex, were also evaluated. Oxotremorine did not modify the initial or "spinal" component of the reflex but markedly reduced the amplitude and increased the latency of the secondary or "supraspinal" phase. Atropine antagonized the inhibitory response. Effects of oxotremorine differed importantly from those produced by baroreceptor and coronary chemoreceptor activation and administration of clonidine and methyldopa which also attenuated the amplitude of the supraspinal component but did not alter its latency. Consequently, oxotremorine depresses sympathetic function at loci within the brainstem and cord by mechanisms not identical with those mediating responses to these reflexes and drugs.


Studies on the cardiovascular depressor actions of ST 91--an analogue of clonidine.

St 91 is an analogue of the alpha-adrenoceptor agonist and antihypertensive agent clonidine. I.v. infusion of St 91 (8 microgram/kg/min, 2 min) produces an immediate but transient pressor response and a prolonged bradycardia but, unlike clonidine, it produces no hypotension, allegedly because this drug does not penetrate the C.N.S. It was found that, after pretreatment with phenoxybenzamine (1.5 mg/kg, i.v.) an infusion of St 91 (8 microgram/kg/min, 2 min) produced a much diminished pressor response and a later small hypotension, while still causing the same degree of bradycardia. Infusion of St 91 (4--16 microgram/kg over 2 min) into the vertebral artery (i.a. vert.) produced dose-dependent hypotension and bradycardia only, which were reversed by piperoxan (300 microgram/kg, intracisternal). There was no significant difference in the potency of St 91 when given i.a. vert. or i.c.m. (5--20 microgram/kg) and the dose-response curves for hypotension and bradycardia were parallel, although the onset of effects was more rapid via the vertebral route. It is suggested that St 91 can cross the blood-brain barrier although why no hypotension is observed after i.v. administration still remains obscure.


Acute and chronic administration of alpha-methyldopa: regional levels of endogenous and alpha-methylated catecholamines in rat brain.

Acute administration of alpha-methyldopa (200 mg kg-1 s.c.) produced a short-lived decrease in dopamine levels in 5 regions of the rat brain. Maximal dopamine depletion was 55% in the corpus striatum and over 75% in other regions and occurred 4--6 h after alpha-methyldopa injection; dopamine levels recovered within 12 h. Maximal noradrenaline depletion of over 80% occurred in all regions 4--24 h after alpha-methyldopa and after 24 h noradrenaline levels were still significantly reduced from control values. In these acute studies alpha-methyldopamine accumulated rapidly in amounts equal to or greater than the depleted dopamine in all regions, reaching a peak at 4 h. By contrast, alpha-methylnoradrenaline accumulated more slowly reaching a peak at 6--24 h and was never present in amounts greater than the depleted noradrenaline. Following chronic administration of alpha-methyldopa (40 mg kg-1 s.c., twice daily 5 days) there was a similar depletion of noradrenaline and dopamine to that seen in the acute studies. The depletion was associated with a much smaller accumulation of alpha-methyldopamine. The striking feature of these results, however, was the large accumulation of alpha-methylnoradrenaline in all brain regions. This probably reflects the slow turnover and resistance to degradation by monoamine oxidase of alpha-methylnoradrenaline.


The anticonvulsant action of L-2,4-diaminobutyric acid.

The GABA uptake inhibitor, L-2,4-diaminobutyric acid (L-DABA) was examined for potential anticonvulsant activity in mice. Given intracerebroventricularly (i.c.v., 2 mumoles) L-DABA almost doubled the CD50 of picrotoxin and 3-mercaptopropionate (3-MP), a glutamate decarboxylase inhibitor--the convulsants being administered 15 min after the L-DABA. The anticonvulsant effect was not observed after 40 min. L-DABA given i.p (5 mmoles/kg) was also anticonvulsant against 3-MP but given i.p. or i.c.v. had no anticonvulsant action against strychnine. The D-isomer of DABA, less active as an inhibitor of GABA uptake, had no anticonvulsant activity against 3-MP and nor did three other inhibitors of GABA uptake, namely nipecotic acid, cis-1,3-aminocyclohexane carboxylic acid (ACHA) and beta-alanine. Possible mechanisms of the anticonvulsant action of L-DABA are discussed.


Antagonism of cholinomimetics by troxypyrrolidinium in guinea-pig atria and longitudinal ileal muscle: comparison with hemicholinium-3.

The inhibitory effect of troxypyrrolidinium (trox) (10(-6) to 2 x 10(-3) M) on responses to carbachol (CCh) and acetylcholine (ACh) was investigated in the electrically stimulated left atrium and longitudinal ileal muscle of the guinea pig. In both tissues, trox exhibited antimuscarinic activity causing parallel shifts of the concentration--response curves to both agonists with no depression of maximum responses. Responses to CCh were inhibited by trox (5 x 10(-4) M) to a greater extent than responses to ACh and this difference was maintained following inhibition of cholinesterases with dyflos. In the guinea-pig atrium using CCh as agonist dose ratios produced by the higher concentrations of trox (greater than 5 x 10(-5) M) were less than expected resulting in a non-linear Arunlakshana--Schild (A-S) plot and this effect of trox was maintained in the presence of mecamylamine (2 x 10(-5) M). In longitudinal ileal muscle flattening of the A-S plot with high concentrations of trox did not occur. Although hemicholinium-3 (HC-3) produces a non-linear A-S plot for antimuscarinic activity in atria the A-S plot obtained with the longitudinal ileal strip using HC-3 (2 x 10(-5) to 2 x 10(-3) M) did not exhibit flattening at high concentrations. The dose ratios obtained with HC-3 (5 x 10(-4) M) using CCh as agonist were significantly greater than those obtained with ACh. It is suggested that trox, like HC-3, acts as a metaffinoid antagonist at the muscarinic receptor.


Effects of anaesthetics and anticonvulsants on the action of kainic acid in the rat hippocampus.

The effects of anaesthetics and anticonvulsants on the acute behavioral response and neurochemical alterations following intrahippocampal injection of kainic acid were examined. When compared to the effects in animals anaesthetized with a combination of chloral hydrate and pentobarbital (Equithesin), brief anaesthesia with ether or with hexobarbital potentiated whereas prolonged anaesthetia attenuated the action of 0.5 microgram of kainic acid. Of the constituents of Equithesin, chloral hydrate offered less protection than pentobarbital. The anticonvulsants, phenobarbital, diazepam, diphenylhydantoin, and carbamazepine offered partial protection when administered in conjunction with ether anaesthetia.


Morphine analgesia and the bulbospinal serotonergic system: increase in concentration of 5-hydroxyindoleacetic acid in the rat spinal cord with analgesics.

Administration of an analgesic dose of morphine increased the concentration of the metabolite of 5-hydroxytryptamine (5HT), 5-hydroxyindoleacetic acid (5HIAA), in the spinal cord of rats. The time course of the change in 5HIAA concentration in the dorsal half of the spinal cord corresponded to that of the morphine analgesia, while such was not the case in the ventral half. When the spinal cord was transected at C1, the effect of morphine on 5HIAA concentration disappeared. After transection at the inter-collicular level, this effect remained. The possible relationship between morphine analgesia and descending serotonergic neurons in the spinal cord is discussed.


Effects of an anabolic steroid and vitamin B complex upon myopathy induced by corticosteroids.

In rats repeatedly treated with dexamethasone, body weight decreased severely, creatine content in urine increased, tetanic contraction of the gastrocnemius muscle decayed easily and twitch tension of the muscle had a slow rise time. In a group of rats given large doses of vitamin B complex along with the anabolic steroid, nandrolone phenylproprionate, all syndromes described above for the dexamethasone-treated rats were prevented, dose dependently by vitamin B complex. The individual components of the vitamin B preparation combined with the nandrolone phenylpropionate partially suppressed the changes induced by dexamethasone. Diphenylhydantoin depressed the slow rise time of twitch tension as effectively as did vitamin B complex with nandrolone phenylpropionate. From the results presented here and facts previously reported it was concluded that the condition of the animals could be well controlled by repeated administration of vitamin B complex with nandrolone phenylpropionate, even though dexamethasone was repeatedly injected.


Distribution and localization of p-hydroxy-d-amphetamine in rat brain.

p-Hydroxy-d-amphetamine (p-OHdA) penetrates the blood--brain barrier poorly, when given acutely or by repeated systemic treatments, or when formed by biotransformation from administered d-amphetamine. However its distribution is relatively selective as it accumulates in the striatum more than in the brainstem. The rate of disappearance also differs in the two areas, being slower in the striatum than in the brainstem. These findings suggest that p-OHdA might be stored in different compartments. To check whether p-OHdA specificially accumulated in nerve terminals, catecholaminergic nerve endings were destroyed with 6-hydroxydopamine (6-OHDA). It has been shown that p-HOdA accumulates much less in the striatum of 6-OHDA-treated rats than of controls. This effect was not present in the brainstem. Accumulation of p-OHdA was similar after repeated d-amphetamine administration. The results are interpreted as showing that p-OHdA tends to accumulate in dopaminergic structures.


Effects of viloxazine, its optical isomers and its major metabolites on biogenic amine uptake mechanisms in vitro and in vivo.

Viloxazine hydrochloride (ICI 58,834, VIVALAN) a chemically novel antidepressant, shows selective inhibition of noradrenaline uptake into mouse heart in vivo and into rat brain in vitro. The noradrenaline uptake inhibitory activity resides primarily in one of the two optically active isomers, and it is suggested that in the conformation adopted for uptake by noradrenaline, the aryl and the amino groups are trans. In a comparison of in vivo and in vitro potency, tri- and tetracyclic antidepressants exhibit a good correlation. However, viloxazine possesses higher in vivo activity than would be expected from in vitro studies. The latter finding cannot be readily explained on the basis of known pharmacokinetic or metabolic factors.


Angiotensin II mediation of adrenal catecholamine secretion induced by intrarenal isoprenaline infusion.

Isoprenaline infusion into the renal artery of the cat induced an increase in the catecholamine (CA) secretion rate from the adrenal gland. CA release by isoprenaline was preferentially noradrenaline. Intravenous infusion of an angiotensin II (A II) antagonist abolished adrenal CA response to intrarenal isoprenaline injection. It is suggested that intrarenal isoprenaline infusion stimulates renal renin release and A II production which, in turn, stimulates adrenal CA secretion.


Chronic effects of 6-hydroxydopamine and reserpine on myocardial adenylate cyclase.

The effects of chronic administration of 6-hydroxydopamine or reserpine on catecholamine-sensitive adenylate cyclase from rat hearts were studied. Not only basal adenylate cyclase activity, but stimulation of the enzyme by norepinephrine, isoproterenol, NaF, guanylyl-imidodiphosphate, or combination of isoproterenol and guanylyl-imidodiphosphate, was significantly increased in the treated than in the control hearts. It is inferred that supersensitivity of myocardial adenylate cyclase following chronic treatment with reserpine or 6-hydroxydopamine may result from an increase in the catalytic activity of the enzyme.