EFFECT OF ANTICONVULSANTS ON EXPERIMENTAL CORTICAL EPILEPSY INDUCED BY TUNGSTIC ACID GEL IN RATS

Abstract

Effects of anticonvulsants were EEG and behaviorally examined on experimental epilepsy induced by cortical application of tungstic acid gel in rats. The animals showed spike, spike and wave complex, and secondary generalized seizure (SGS) with high frequency components on EEG within 1 h after the gel application. Such SGS often recurred with a constant interictal period over 2-3 h. Behaviorally, head twitching, forelimb clonus and violent convulsion with kangaroo posture occurred. Diphenylhydantoin Na (10-40 mg/kg i.v.), phenobarbital NA (20, 40 mg/kg) and diazepam (0.5-2.0 mg/kg) shortened the duration of SGS and prolonged the interictal period. Trimethadione and dipropylacetate Na (160 mg/kg) shortened the duration but did not change the interictal period. Diazepam, dipropylacetate and taurine suppressed the interictal spikes. These drugs, except taurine, depressed kangaroo posture and changed it to weaker convulsive behavior. Apparently the epileptic model is suitable for predicting the effectiveness of a potential anticonvulsant in the epilepsies associated with the cortex and for elucidating its mode of action.