Effect of acetazolamide on the anticonvulsant potency of phenobarbital in mice.

Publisher Website
Google Scholar
Abstract
Effect of acetazolamide (AZA) on the anticonvulsant potency of phenobarbital (PHB) was investigated in mice by maximal electroshock seizure (MES) test. By coadministration with AZA a remarkable increase and prolongation of the anticonvulsant activity of PHB was evoked. The type of the synergism of PHB with AZA was not additive but of potentiation. The potentiation of the anticonvulsant activity of PHB with AZA was related to inhibition of carbonic anhydrase (CA) in brain rather than in blood. The anticonvulsant activity of PHB was also increased by coadministration with me-thazolamide which greatly inhibited brain CA. Furosemide, which had no inhibitory effect on brain CA, failed to show any potentiation of the anticonvulsant activity of PHB. The inhibition of brain CA may play a significant role in the potentiation of the anticonvulsant activity of PHB. Although reserpinization completely abolished the protective effect of AZA on MES, the potentiation of the anticonvulsant activity of PHB was still observed by AZA. Pharmacodynamic and/or pharmacokinetic effects of AZA independent of its anticonvulsant action may contribute to the potentiation of the PHB action.