Estudo eletrofisiologico da epileptogenese em animais submetidos a multiplos status epilepticus duranmte o desenvolvimento

Abstract

Previous experimental data have shown that neonatal seizures produces several abnormalities which persist in the aduit life. Pilocarpine-induction of consecutive status epilepticus in P7-9 rat pups of severe behavioral and eiectrographic disturbances (hippocampal and neocorticai epiieptiform discharges) in adulthood. Hippocampal slice experiments were undertaken in adult rats to explore some eietrophysiological mechanisms associated with chronic epileptogenesis in such animals. Standard extracellular recordings from CA1 area show an epileptiform responses in animals subjected to neonatal seizures These evoked responses were characterized by multiple population spikes in normal saline (3.5 mM K+). Higher potassium concentration (7.5 mM) promote increased local hyperexcitability mainly subthreshold rebount bursts and spontaneous discharges. The present data demonstrate a chronic hippocampal hyperexcitability as a consequence of multipie seizures in the neonatal period of life