RESUMO
OBJECTIVE: To investigate the anticonvulsion effect of 4-amino-2-methyl cantharidinmide (AMC) and its influences on epileptiform electroencephalogram (EcoG), contents of γ-aminobutyric acid (GABA) and GABAB receptor. METHODS: Rat model of penicillin-induced-convulsion (PIC) was established by intracortical (ic) penicillin (PNC) injection in rat motor cortex. Valproate (VPA) was used as the positive control drug. Convulsion seizure latency and racine behavior study graduations were used as indexes to evaluate the efficacy. RM6240C multi-channel biological signal collection-processing system synchronously recorded EcoG of convulsive rats after intragastric (ig) administration of AMC (25.0, 100.0 mg · kg-1). The effects on convulsion and epileptiform discharge were analyzed. The contents of GABA and the expression of GABAB receptor in the cortex and hippocampus regions of rats were determined by immunohistochemistry technique. RESULTS: AMC at the two doses and VPA could reduce epileptiform activities and discharge and prolong the latencies of epilepsy seizure, compared with the PIC group (P 0.05); compared with model control, the expression quantity of hippocampal GABAB receptor protein was significantly increased (P 0.05). GABA expression quantity in groups of larger dosage AMC and VPA were respectively higher than that in the normal group and the model group, and the GABAB receptor protein expression quantity also significantly increased (P < 0.05). CONCLUSION AMC can antagonize the convulsion seizure and inhibit the epileptiform discharge induced by penicillin in rats. The anti-convulsion mechanism of AMC is possibly related with increasing GABA content and GABAB receptor expression in cortex and the hippocampus. Copyright 2012 by the Chinese Pharmaceutical Association.