Depolarization-induced suppression of GABAergic inhibition in rat hippocampal pyramidal cells: G protein involvement in a presynaptic mechanism

doi:10.1016/0896-6273(94)90430-8

Neuron

Volume 13, Issue 6, December 1994, Pages 1447-1455

https://doi.org/10.1016/0896-6273(94)90430-8 Get rights and content

Summary

Following postsynaptic activation of a pyramidal cell, the degree of GABAergic synaptic inhibition that the cell receives is reduced dramatically for many seconds. Previously, we found that induction of depolarizationinduced suppression of inhibition (DSI) required postsynaptic increases in intracellular [Ca²⁺], but absence of a decrease in responsiveness to iontophoretically applied GABA left the mechanism of DSI expression uncertain. We investigated DSI with whole-cell voltage-clamp recordings in rat hippocampal slices. Bath-applied carbachol was ordinarily used to increase the spontaneous action potential-induced IPSCs (slPSCs) and enhance detectability of DSI; synaptically released ACh has the same effects. TTX-sensitive slPSCs are markedly reduced by DSI, whereas TTX-insensitive miniature IPSC amplitudes do not change, suggesting that DSI represents a retrograde influence on presynaptic GABA release. A lag (∼ 1 s) prior to maximal DSI and prevention of DSI by pertussis toxin pointed to a G protein-linked second messenger that may be presynaptic, since perturbation of postsynaptic G protein function did not alter DSI.

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Neuron

Depolarization-induced suppression of GABAergic inhibition in rat hippocampal pyramidal cells: G protein involvement in a presynaptic mechanism

Summary

Brain Res.

Brain Res. Rev.

J. Neurosci. Meth.

Life Sci.

Brain Res.

Neuron

Neurosci. Lett.

J. Neurosci. Meth.

Neuron

Brain Res.

Int. Rev. Neurobiol.

Neuron

Neuron

Gating of GABAergic inhibition in hippocampal pyramidal cells

Ann. NY Acad. Sci.

Pathway of postsynaptic inhibition in the hippocampus

J. Neurophysiol.

A G protein couples serotonin and GABAB receptors to the same channels in hippocampus

Science

A G protein couples serotonin and GABA_B receptors to the same channels in hippocampus