Taurine inhibits rat substantia nigra pars reticulata neurons by activation of GABA- and glycine-linked chloride conductance.
Whole-cell recordings from rat midbrain slices showed that bath application of taurine (30 microM-10 mM) reversibly hyperpolarized and inhibited the firing of substantia nigra pars reticulata neurons. These effects were mediated by an increase in membrane chloride conductance. Taurine cross-desensitized with GABA and glycine. Strychnine competitively antagonized the actions of glycine and taurine but not that of GABA. On the other hand, the responses to taurine and glycine were not sensitive to bicuculline. These findings suggest that taurine inhibits SNR neurons by opening GABA and glycine-linked chloride channels.
Ye
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G
Department of Physiology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin.
Tse
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Yung
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D000818:Animals; D001640:Bicuculline / Q000494:pharmacology; D018118:Chloride Channels / Q000187:drug effects / Q000378:metabolism*; D004594:Electrophysiology; D018756:GABA Antagonists / Q000494:pharmacology; D005998:Glycine / Q000502:physiology*; D018408:Patch-Clamp Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D011963:Receptors, GABA-A / Q000187:drug effects; D018009:Receptors, Glycine / Q000187:drug effects; D013378:Substantia Nigra / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D013654:Taurine / Q000494:pharmacology*; D005680:gamma-Aminobutyric Acid / Q000502:physiology*
D018118:Chloride Channels; D018756:GABA Antagonists; D011963:Receptors, GABA-A; D018009:Receptors, Glycine; D013654:Taurine; D005680:gamma-Aminobutyric Acid; D005998:Glycine; D001640:Bicuculline