Effects of anticonvulsants on hippocampus-generating seizures

Acute effects of 4 anticonvulsants on hippocampal kindled seizures induced with about 3 Hz electrical stimulations were assessed in cats. The number of stimulating pulses required for the triggering of epileptic afterdischarge (pulse-number threshold, PNT) was used as the indicator for the seizure threshold. Duration of afterdischarge (ADD), ictal and interictal behaviors and serum drug levels were also recorded. PB produced a PNT-increase more prominently than an ADD-decrease with seizure stage regression. PHT produced only a proconvulsive effect by decreasing PNT. CBZ also produced a proconvulsive effect by decreasing PNT at a low dose, and decreased PNT and ADD simultaneously at a high dose. Conversely VPA increased PNT and ADD simultaneously. These results were discussed comparing mainly with a previous study of amygdala-generating seizures.