[Responses of neurons of an isolated cortical strip in a state of convulsive excitation to single electrical stimuli]. / Reaktsii neironov izolirovannoi poloski kory golovnogo mozga, nakhodiashchikhsia v sostoianii sudorozhnogo vozbuzdeniia, na odinochnye élektricheskie razdrazheniia.

ABSTRACT

Responses of isolated cortical slab neurons to single stimuli before, during and after the development of epileptiform state in a slab were investigated in experiments on immobilized and locally anaesthetized cats. It was shown that during the development of generalized seizure activity in an isolated cortical slab its neurons generate EPSP and paroxysmal depolarizing shifts (PDS) of the membrane potential (MP) accompanied by refractory periods. Refractory periods coincide with PDS plato and MP repolarizing shifts. During these shifts single electrical stimuli produce gradually transforming PDS. After cessation of the ictal activity neurons are still able to generate PDS to single stimuli for some time. It is suggested that the role of postsynaptic responses in genesis of the epileptiform activity is not the most important. Nonsynaptic factors are, probably, involved in its generation.