Brief Communication Low Ethanol Concentrations Selectively Augment the Tonic Inhibition Mediated by Subunit-Containing GABAA Receptors in Hippocampal Neurons
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چکیده
In central neurons, a tonic conductance is activated by ambient levels of the inhibitory transmitter GABA. Here, we show that in dentate gyrus granule cells, where tonic inhibition is mediated by subunit-containing GABAA receptors, this conductance is augmented by low concentrations (30 mM) of ethanol. In contrast, the tonic inhibition mediated by 5 subunit-containing receptors of CA1 pyramidal cells is not affected. The effect of ethanol on tonic inhibition specifically reduces the excitability of the dentate gyrus and identifies the subunit-dependent tonic inhibition as a likely site of ethanol action in the brain.
منابع مشابه
Low ethanol concentrations selectively augment the tonic inhibition mediated by delta subunit-containing GABAA receptors in hippocampal neurons.
In central neurons, a tonic conductance is activated by ambient levels of the inhibitory transmitter GABA. Here, we show that in dentate gyrus granule cells, where tonic inhibition is mediated by delta subunit-containing GABA(A) receptors, this conductance is augmented by low concentrations (30 mM) of ethanol. In contrast, the tonic inhibition mediated by alpha5 subunit-containing receptors of ...
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