Giant synaptic potential hypothesis for epileptiform activity.

D Johnston; T H Brown

doi:10.1126/science.7444469

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PubMed · 7444469

Giant synaptic potential hypothesis for epileptiform activity.

D Johnston·T H Brown

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Abstract

According to one hypothesis, the paroxysmal depolarizing shift observed in the penicillin model of epilepsy results from a giant excitatory postsynaptic potential. This hypothesis has recently been questioned, primarily because it has never been subjected to rigorous experimental examination. Four quantitative predictions were derived from this hypothesis and tested in CA3 pyramidal neurons of the hippocampus. The four critical predictions concern the behavior of the paroxysmal depolarizing shift under current- and voltage-clamp conditions as a function of membrane potential. The experiments confirmed all four predictions.

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Action Potentials Animals Disease Models, Animal Electric Conductivity Epilepsy Guinea Pigs Hippocampus In Vitro Techniques Membrane Potentials Penicillin G Synaptic Membranes Journal Article Research Support, U.S. Gov't, P.H.S.

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D Johnston, T H Brown. 1981-01-16. Giant synaptic potential hypothesis for epileptiform activity.. https://doi.org/10.1126/science.7444469

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