Abstract

The anticonvulsant properties of acetazoleamide were investigated in rats and mice and compared with those of carbon dioxide. Both agents increase electroshock seizure threshold and abolish the tonic extensor phase of maximal electroshock seizures. Tolerance develops to the repeated administration of acetazoleamide and, concurrently, cross-tolerance is exhibited to carbon dioxide. Nitrate ion, which also inhibits carbonic anhydrase, possesses anticonvulsant properties similar to acetazoleamide. It is proposed that the anticonvulsant effect observed after carbonic anhydrase inhibition is due to an increased steady-state concentration of carbonic acid within brain cells.