[Effect of sodium valproate on bicuculline-induced epileptiform activity in rat hippocampal slices in vitro]

Experiments were conducted on the rat hippocampal slices in vitro with the superfusion of bicuculline (Bcl, 10 mumol/L) and stimulation of Schaffer collaterals by single pulse to produce epileptiform activity of the pyramidal cells in CA1 area. In these experiments the effect of constant microinjection of sodium valproate onto the surface of slice on the epileptiform activity was studied. The results showed that the valproate, in concentration of 20, 30, 50 and 100 mmol/L, inhibited the Bcl-induced epileptiform activity in a manner of dose-dependence. It was deduced that the inhibition of epileptiform activity by the valproate is possibly related to the recovery of and increase in the inhibition mediated by GABAergic neurons and may be also to the non-synaptic mechanism of the valproate in rat hippocampus.