Neuroactive steroids reduce neuronal excitability by selectively enhancing tonic inhibition mediated by δ subunit-containing GABAA receptors

  title={Neuroactive steroids reduce neuronal excitability by selectively enhancing tonic inhibition mediated by $\delta$ subunit-containing GABAA receptors},
  author={Brandon M. Stell and Stephen G Brickley and C Y Tang and Mark Farrant and Istv{\'a}n M{\'o}dy},
  journal={Proceedings of the National Academy of Sciences of the United States of America},
  pages={14439 - 14444}
  • B. Stell, S. Brickley, I. Módy
  • Published 17 November 2003
  • Biology, Psychology
  • Proceedings of the National Academy of Sciences of the United States of America
Neuroactive steroids are potent modulators of γ-aminobutyric acid type A receptors (GABAARs), and their behavioral effects are generally viewed in terms of altered inhibitory synaptic transmission. Here we report that, at concentrations known to occur in vivo, neuroactive steroids specifically enhance a tonic inhibitory conductance in central neurons that is mediated by extrasynaptic δ subunit-containing GABAARs. The neurosteroid-induced augmentation of this tonic conductance decreases neuronal… 

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