过刊浏览

失血性休克引起大鼠肠系膜动脉平滑肌依钙K~(+)通道活动改变

开丽, 胡德耀, 王中峰, 施玉#[94]liang, 刘良明

第三军医大学大坪医院野战外科研究所.重庆 400042；中科院上海生命科学研究院,上海生理研究所.上海 200031

摘要

在由股动脉放血制备的失血性休克大鼠模型急性分离的肠系膜动脉平滑肌细胞上,利用膜片箝单通道记录技术观察了血管平滑肌依钙K~(+)通道(BK_(Ca))的活动。发现在对去甲肾上腺素(NE)反应性增高的休克代偿期,BK_(Ca)的开放概率(P)_(o))和单位电导都显著较正常动物的低, P_(o)的改变主要是由通道的慢关闭时间常数(#tau#_(cs))增大引起关闭时间延长所致;而处于对NE反应性降低的休克失代偿期,BK_(Ca)的P_(o)和单位电导都高于正常动物,P_(o)的变化也主要是#tau#_(cs)减小所致。

关键词： 失血性休克; 血管对去甲肾上腺素的反应性; 大电导钙激活钾通道; 血管平滑肌细胞; 肠系膜动脉

Hemorrhagic shock induces changes in large-conductance Ca~(2+)-dependent K~(+) channel activity in mesenteric arterial smooth muscle cells of rats

Kai Li, Hu Deyao, Wang Zhongfeng, Shi Yuliang, Liu Liangming

Research Institute of Surgery,Daping Hospital,Third Military Medical University.Chongqing 400042；China

Abstract

The results showed that the BK_(Ca) activity was inhibited with decreased open probability (P_(o)) and single-channel conductance. The decrease of P_(o) resulted from an increase of the close time constant (#tau#_(cs)) in the compensatory stage of HS, i.e. the term of hyperresponse of the muscle to norepinephrine (NE) (HS lasted for about 40 min). During the decompensation stage of HS, i.e. the period of hyporesponse to NE (HS developed for 3 h), the BK_(Ca) activity was enhanced with the increase in single-channel conductance and P_(o) which was a result of a decrease in #tau#_(cs).

Key words: Hemorrhagic shock;Vascular response to norepinephrine;Large-conductance calcium-activated potassium channel;Vascular smooth muscle cell;Mesenteric artery

收稿日期：　　录用日期：

通讯作者：　　E-mail:

引用本文：

开丽, 胡德耀, 王中峰, 施玉#[94]liang, 刘良明. 失血性休克引起大鼠肠系膜动脉平滑肌依钙K~(+)通道活动改变[J]. 生理学报 2001; 53 (4): .

Kai Li, Hu Deyao, Wang Zhongfeng, Shi Yuliang, Liu Liangming. Hemorrhagic shock induces changes in large-conductance Ca~(2+)-dependent K~(+) channel activity in mesenteric arterial smooth muscle cells of rats. Acta Physiol Sin 2001; 53 (4): (in Chinese with English abstract).