The effects of 6 weeks of oral clonidine hydrochloride (0.05 mg b.i.d.) on the cardiovascular response to stressful mental arithmetic (SMA) were studied in menopausal women. There was no significant alteration in resting limb blood flow after oral clonidine. The rise in forearm blood flow during SMA was, however, greater and the return to basal levels after SMA slower in women treated with clonidine than in the initial control test. Hand blood flow and pulse rate changes during SMA were unaffected by clonidine. These findings, in keeping with our previous observations of the change in vascular response to exogenous amines after clonidine therapy, are difficult to explain in terms of an influence of the drug on presynaptic alpha-adrenergic activity alone. It is therefore possible that clonidine might affect other mechanisms such as peripheral cholinergic activity.
Adult Blood Flow Velocity