Abstract
Neuronal response in the strychninized cortical suprasylvian gyrus was investigated in experiments on immobilized and unanesthetized cats using intracellular techniques. Paroxysmal depolarizing shifts (PDS) in neuronal membrane potential were recorded, consisting of a bursting discharge and slow depolarization wave. It was found when using intracortical stimulation that PDS can accumulate and change in shape and size. Bursting discharges in PDS were induced by large-scale EPSP which could be distinguished from paroxysmal response. Data from presumably intradendritic readings demonstrated the presence of large-scale EPSP during the generation of epileptiform discharges in the cortex. In a proportion of cells, PDS were accompanied by hyperpolarizing potentials — apparently IPSP, since they undergo reversal with intercellular administration of Cl−. The contribution of excitatory and inhibitory synaptic influences to paroxysmal neuronal response is discussed.
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I. I. Mechnikov State University, Odessa. Translated from Neirofiologiya, Vol. 22, No. 5, pp. 642–649, September–October, 1990.
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Lopantsev, V.É., Taranenko, V.D. & Odintsova, T.B. Postsynaptic components of paroxysmal neuronal response in the strychninized neocortex. Neurophysiology 22, 474–481 (1990). https://doi.org/10.1007/BF01052518
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DOI: https://doi.org/10.1007/BF01052518