There does not appear to be a consensus on the normal values of cerebrospinal fluid pressure (Pcsf) in rats because of the different conditions in which each experiment has been done. Anaesthesia, restraint or recordings from different anatomical places and the use of simultaneous infusions could produce a great variability in the obtained results and because of that the average Pcsf in rats has been reported to be between 2 and about 18.5 cm H2O. The aim of this study is to provide new information about the normal values of Pcsf in adult, conscious rats by carrying out long-term measurements, for 3 consecutive days, from different anatomical places. Thirty male Wistar rats divided in three experimental groups of ten animals each were used. A catheter of silicone was implanted into the lateral ventricles in group I, the cisterna magna in group II, and the lumbar subarachnoid space in group III to record the Pcsf values. This catheter was attached to a swivel system to allow unrestrained and free behaviour in the rats. Mean values of normal Pcsf values were 13.03 +/- 0.73 cm H2O from the lateral ventricles, 15.9 +/- 0.73 cm H2O from the cisterna magna, and 16.73 +/- 1.14 cm H2O from the lumbar subarachnoid space.
Anesthesia Animals