挥发性麻醉剂对培养海马神经元中高电导钙依赖性钾通道的影响。

Effects of volatile anaesthetics on a high conductance calcium dependent potassium channel in cultured hippocampal neurons.

作者信息

McLarnon J, Sawyer D

机构信息

Department of Pharmacology and Therapeutics, Faculty of Medicine, The University of British Columbia, Vancouver, Canada.

出版信息

Toxicol Lett. 1998 Nov 23;100-101:271-6. doi: 10.1016/s0378-4274(98)00195-7.

DOI:10.1016/s0378-4274(98)00195-7

PMID:10049153

Abstract

(1) The effects of isoflurane and halothane (at nominal concentrations of 4%) were studied on a high conductance Ca2+-dependent K+ channel using inside-out patches from cultured rat hippocampal neurons. (2) With physiological-like concentrations of K+ across patches (140 mM internal and 5 mM external), unitary activity from a 4 pA channel (conductance near 100 pS) was evident in excised patches. (3) Isoflurane or halothane had no effects on unitary properties of K (Ca) including channel amplitudes and open and closed times. The channel open probability was also unchanged in the presence of the volatile agent. The results suggest that macroscopic high conductance K (Ca) currents in hippocampal neurons would be relatively insensitive to high concentrations of inhalational anaesthetics.

摘要

(1) 使用培养的大鼠海马神经元的内向外膜片，研究了异氟烷和氟烷（标称浓度为4%）对高电导钙依赖性钾通道的影响。(2) 在膜片两侧具有生理浓度的钾离子（内膜140 mM，外膜5 mM）时，在切除的膜片中，4 pA通道（电导接近100 pS）的单位活性明显。(3) 异氟烷或氟烷对钾（钙）通道的单位特性没有影响，包括通道幅度、开放和关闭时间。在挥发性麻醉剂存在的情况下，通道开放概率也未改变。结果表明，海马神经元中的宏观高电导钾（钙）电流对高浓度吸入麻醉剂相对不敏感。