Effect of Verapamil, Cinnarizine and Memantine on Maximal Electroshock, Picrotoxin, and Pilocarpine-Induced Seizure Models in Albino Mice

Verapamil and cinnarizine block L and T-type calcium channels respectively. Memantine is an N-methyl-D-aspartate (NMDA) receptor antagonist. Ca2+-channel blockers (CCBs) and memantine, each decrease Ca2+ entry to the neuronal cell by different mechanisms. Inhibition of the inward flow of calcium ions could depress the epileptic depolarization of neurons. The aim of the present work is to assess effects of verapamil, cinnarizine and memantine on experimentally induced convulsions in albino mice. Methods: Maximal electroshock, picrotoxin and pilocarpine-induced seizure models were utilized. Results: Verapamil decreased the mean latency period in pilocarpine model. Cinnarizine increased the mean latency period and partially protected from convulsions in picrotoxin model. The drug completely prevented the occurrence of convulsions in pilocarpine model. Memantine increased the electroconvulsive threshold in maximal electroshock model. In pilocarpine model, the mean latency period was increased while, decreased in picrotoxin model after administration of memantine. Conclusion: Verapamil potentiated seizure occurrence in pilocarpine model. Cinnarizine protected from convulsions, partially in picrotoxin and completely in pilocarpine models. Memantine had anticonvulsant effect in maximal electroshock and pilocarpine models but, potentiated the occurrence of seizures in picrotoxin model.