CARBONIC ANHYDRASE INHIBITION. VI. THE EFFECT OF ACETAZOLAMIDE ON CEREBROSPINAL FLUID FLOW

¹ Experimental Therapeutics Section, Research Division, American Cyanamid Company, Stamford, Connecticut

We confirm the work of Tschirgi et al. (1954), showing that acetazolamide reduces CSF flow rate in the cat. There appear to be at least three characteristics of this response.

The flow rate declines to approximately 30 per cent of control rates, and appears independent of dose of acetazolamide in the range of 0.5 to 150 mgm./kgm.

The onset of the effect occurs within 5 minutes, reaches a maximum within 30 minutes, and persists for several hours following acetazolamide at 1 to 150 mgm./kgm.

Work with CL 8490 and CL 13850 shows that compounds closely resembling acetazolamide chemically, but without action against carbonic anhydrase, have no effect on CSF flow. The decline in CSF flow following acetazolamide thus appears due to its effect on inhibition of this enzyme. No effect of acetazolamide apart from its action on carbonic anhydrase has been reported.