Effects of some antiepileptics on septal-kindled seizures in rats

Abstract

Purpose The present study was performed to understand the characteristics of septal kindling in rats, especially the efficacies of antiepileptic drugs in comparison with amygdala kindling. Methods Under pentobarbital anesthesia, rats were fixed to a stereotaxic apparatus, and electrodes were implanted into the right frontal cortex, the hippocampus, the lateral septal and the amygdala. Electrodes were connected to a miniature receptacle, which was embedded in the skull with dental cement. Bipolar stimulation was applied to the lateral septal or the amygdala every day until a generalized seizure was obtained. Carbamazepine (CBZ), zonisamide (ZNS) and clobazam (CLB) were orally administered to fully kindled rats. Result A considerable number of stimulations was required to establish septal-kindled seizures. In addition, wet dog shakes were observed during the septal kindling procedure, different from amygdala kindling. The oral administration of CBZ, ZNS and CLB caused a dose-dependent inhibition both of seizure stage and after-discharge (AD) duration of septal-kindled seizures. CBZ and ZNS caused a more potent inhibition of septal-kindled seizures than amygdala kindled seizures, whereas CLB inhibited both septal and amygdala kindled seizures to almost the same extent. Conclusion Septal kindling was confirmed to possess some characteristics, which were evidently different from that of amygdala kindling. In addition, it was demonstrated that septal kindling was also available as a model for the evaluation of antiepileptic drugs.