Receptors with different affinities mediate phasic and tonic GABAA conductances in hippocampal neurons -: art. no. RC223

被引：268

作者：

Stell, BM

Mody, I

机构：

[1] Univ Calif Los Angeles, Sch Med, Dept Neurol, Los Angeles, CA 90095 USA

[2] Univ Calif Los Angeles, Sch Med, Interdepartmental Program Mol Cellular & Integrat, Los Angeles, CA 90095 USA

[3] Univ Calif Los Angeles, Sch Med, Dept Physiol, Los Angeles, CA 90095 USA

来源：

JOURNAL OF NEUROSCIENCE | 2002年 / 22卷 / 10期

关键词：

GABA affinity; tonic inhibition; phasic inhibition; competitive GABA(A) antagonist; SR95531; IPSC amplitude quantification;

D O I：

10.1523/JNEUROSCI.22-10-j0003.2002

中图分类号：

Q189 [神经科学];

学科分类号：

071006 ;

摘要：

A tonic inhibitory conductance mediated by GABA(A) receptors that supplements the phasic inhibition produced by IPSCs has been identified in the hippocampus and cerebellum. It is presently unknown whether tonic and phasic inhibitions are mediated by GABA(A) receptors with different subunit assemblies. Here we demonstrate that a low concentration (200 nM) of the highly specific competitive GABA(A) antagonist SR95531 (gabazine) reduces phasic inhibition in hippocampal granule cells by 71% but has no effect on tonic inhibition, whereas a high concentration (10 muM) of the antagonist blocked both conductances. These findings are consistent with tonic and phasic conductances being mediated by different GABA(A) receptor subtypes with different affinities for GABA.

引用

页数：5

共 28 条

[1] Absence of association between δ and γ2 subunits in native GABAA receptors from rat brain [J].