Halothane increases the open probability of glycine-activated channel current in rat central neurones.
Glycine-activated single-channel currents in rat central neurones were recorded using the outside-out mode of the patch-clamp technique. The unitary conductance of the current was 21 pS. The current evoked by 10 microM glycine had a mean burst duration of 47.8 (2.6) ms and open probability of 0.09 (0.016). Halothane (1 mM) increased the open probability to 0.19 (0.03) without changing either unitary conductance or burst duration. These results suggest that halothane increased the open probability via an increase in the affinity of the receptor for the agonist. Potentiation of the glycine response may reduce excitability of postsynaptic neurones and may contribute to general anaesthesia produced by volatile agents.
Department of Information Physiology, National Institute for Physiological Sciences, Okazaki, Japan.
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M
Wakamori
Y
Y
Ikemoto
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Yamashita
D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D004357:Drug Synergism; D005998:Glycine / Q000494:pharmacology*; D006221:Halothane / Q000494:pharmacology*; D015640:Ion Channel Gating / Q000187:drug effects; D007473:Ion Channels / Q000187:drug effects*; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D018408:Patch-Clamp Techniques; D051381:Rats; D017208:Rats, Wistar
D018685:Anesthetics, Inhalation; D000894:Anti-Inflammatory Agents, Non-Steroidal; D007473:Ion Channels; D005998:Glycine; D006221:Halothane