THE EFFECT OF HYPOXIA ON THE EPILEPTIFORM ACTIVITIES INDUCED BY MAGNESIUM-FREE MEDIUM IN RAT-BRAIN SLICES

In order to understand the mechanisms underlying the seizure generation, the present study has investigated the effect of hypoxia on the transition between seizure and interictal bursting. Bathing rat brain slices of the hippocampus and entorhinal cortex in magnesium-free medium elicits electrographic seizures. However, they are eventually replaced by the interictal bursts. It has previously been shown that the interictal bursts, arising in the hippocampal area CA3, are propagated to and disrupt the seizure generation in the entorhinal cortex. In this report we demonstrate that hypoxia promotes the seizure reappearance in the entorhinal cortex by suppressing the interictal bursts in CA3.