R. L. MacDonald, J. Barker
Jun 1, 1977
Citations
2
Influential Citations
255
Citations
Quality indicators
Journal
Nature
Abstract
PENTYLENETETRAZOL (PTZ) and penicillin (PCN) are potent convulsants commonly used to produce focal or generalised epileptiform discharges in the mammalian central nervous system1. Investigations of the cellular basis for their con-vulsant effects have been performed in various vertebrate and invertebrate preparations wtih two basic hypotheses dominating the literature: (1) that the convulsant effect is produced by pharmacological actions on synaptic transmissions to reduce inhibition2–8 and/or to enhance excitation9, or (2) that the convulsants directly enhance the excitability of neuronal membranes apart from effects on synaptic transmission10–16. We have studied the mechanism of their convulsant action in a mammalian tissue culture system and report here that both PTZ and PCN selectively antagonise post-synaptic responses to γ-aminobutyric acid (GABA), a putative inhibitory neurotransmitter17. The results presented here provide direct evidence derived from the mammalian nervous system that the convulsant action of PTZ and PCN may be due ito a specific pharmacological action on GABA-mediated inhibitory synaptic transmission.