【摘要】 目的：研究Mg2+对猪冠脉平滑肌细胞钙激活钾通道的作用，以揭示Mg2+扩血管作用的电生理机制。方法：应用膜片钳制技术inside－out方式记录冠脉平滑肌上的单通道活动，经PCLAMP软件进行微机采样储存数据和数据的分析处理。结果：Mg2+对猪冠脉平滑肌钙激活钾通道具有明显激活作用：增强通道开放概率P0，增加膜片通道开放数目。结论：Mg2+对钙激活钾通道的激活作用可能为Mg2+调节心血管活动的重要机制之一。更多还原

【Abstract】 Objective: Effects of Mg2+ on Ca2+ - activated K+ channel (Kca) in porcine coronary arterial smooth muscle cells were studied to reveal the electrophysiological mechanism about the effects of mg2+ on the dilatation of blood vessel. Methods: Inside-out method of patch clamp technique was used to record the activity of single channel, configurational application of PCLAMP-software for data sampling storing and analysis. Results: After magnesium was applied to the cytoplasmic face of the channels, activation of Mg2+ on Kca was observed: it increased dose-dependently their open probability(Po) and the numbers of open Ietels of channel in a patch. Conclusions: The activation of Mg2+on Bkca channel may be important in its regulation of cardiovasclar system.更多还原