激活线粒体钙激活钾通道加强心脏停搏液心肌保护作用的观察

目的:探讨线粒体钙激活钾通道(mitochondrial Ca2+-activated K+channels,mitoKCa)的激活是否加强改良St.Thomas心脏停搏液的心肌保护作用。方法:采用离体大鼠心脏灌流方法,全心停灌30 min和复灌60 min复制局部缺血/再灌注损伤模型;实验分单纯缺血复灌组、改良St.Thomas停搏液组、改良St.Thomas停搏液+NS1619组和改良St.Thomas停搏液+NS1619+Paxilline组,观察各组心室力学指标、冠状动脉流出液中乳酸脱氢酶(LDH)含量及心肌含水量的变化。结果:与单纯缺血/复灌组比较,改良St.Thomas停搏液组左心室舒张末期压力抬高程度下降(P<0.01),做功增加(P<0.01),冠状动脉流量增加(P<0.05),心肌含水量减少(P<0.01),LDH释放减少(P<0.01);与St.Thomas停搏液组比较,线粒体钙激活钾通道激动剂NS1619能进一步降低St.Thomas停搏液灌注时LDH的释放(P<0.01),心肌含水量进一步降低,促进左心室功能的恢复(P<0.01);线粒体钙激活钾通道阻断剂Paxilline取消了NS1619的作用(P<0.05~P<0.01)。结论:线粒体钙激活钾通道的激活可加强心脏停搏液的心肌保护作用。

Observation on activation of mitochondrial calcium activated potassium channel to potentiate the cardioplegic solution of cardioplegia

Objective:To investigate whether the activation of mitochondrial calcium activated potassium channel(mitoKCa) can potentiate the cardioplegic solution of modified St.Thomas cardioplegia in isolated rat hearts subjected to ischemia and reperfusion.Methods:The isolated perfused rat hearts were subjected to 30 min global ischemia and 120 min reperfusion.The rats were divided into four groups:ischemia and reperfusion group;modified St.Thomas cardioplegia group;modified St.Thomas cardioplegia+NS1619 group and mo...