Effect of certain drugs on cerebrospinal fluid production in the dog

Abstract

Cerebrospinal fluid (CSF) production rates were measured in the dog by ventriculocisternal perfusion with inulin containing buffer. Normal CSF production rate was found to be about 0.05 ml/min which represents a turnover of 0.4%/min. After intravenous administration of the carbonic anhydrase inhibitors, acetazolamide and methazolamide, a 40–50% decrease in CSF production occurred. An increase in plasma pCO₂, by allowing the animals to inhale 95% oxygen, 5% CO₂, did not result in any significant change in CSF production. Both intravenous and intrathecal administration of varying doses of the cardiac glycoside, ouabain, did not cause any significant change in CSF production rates. It is concluded that CSF production, in part, is controlled by a carbonic anhydrase system.