二氮嗪预处理对大鼠缺血性损伤心肌线粒体功能的保护作用  

Preconditioning with mitochondrial ATP-sensitive potassium channel opener,diazoxide,protects the myocardial mitochondial functions after ischemic injury in rats

作　　者：黄河[1] 肖颖彬[1] 杨天德[2] 李洪[2] 李永旺[2] 

机构地区：[1]第三军医大学新桥医院全军心血管外科中心,重庆400037 [2]第三军医大学新桥医院麻醉科,重庆400037

出　　处：《第三军医大学学报》2008年第9期807-809,共3页Journal of Third Military Medical University

基　　金：国家自然科学基金(30500211)~~

摘　　要：目的探讨线粒体ATP敏感性钾通道开放剂二氮嗪预处理对大鼠心肌细胞线粒体功能保护作用。方法采用大鼠异丙肾上腺素心肌损伤模型,30只大鼠分成对照组、异丙肾上腺素(ISO)损伤组、二氮嗪(DZ)预处理组;以氧电极法测线粒体呼吸,罗丹明123为荧光探针测定线粒体膜电位,采用定磷法检测Na+-K+-ATP酶和Ca2+-ATP酶活性。比较各组心肌细胞线粒体Ⅲ态呼吸速率、线粒体Ⅳ态呼吸速率、线粒体呼吸控制率和线粒体膜电位以及线粒体ATP酶的活性。结果ISO组线粒体Ⅲ态呼吸速率呼吸控制率、线粒体膜电位以及Na+-K+-ATP酶和Ca2+-ATP酶活性与对照组比较显著下降(P<0.01);DZ预处理组Ⅲ态呼吸速率、呼吸控制率和线粒体膜电位(P<0.05)以及Na+-K+-ATP酶和Ca2+-ATP酶活性较对照组低(P<0.01),但与ISO组比较明显恢复。各组对Ⅳ态呼吸速率没有明显影响。结论线粒体ATP敏感性钾通道开放剂二氮嗪能增强心肌细胞线粒体酶活性,产生预处理心肌细胞线粒体保护效应。Objective To investigate the effect of preconditioning with mitochondrial ATP-sensitive potassium channel opener on the mitochondrial functions. Methods Thirty SD rats were used. Isoproterenol was used to induce myocardial ischemic injury in 20 rats, ten of which were pretreated with diazoxide. Rhodamine123 （Rh123） was used as fluorescent prober to measure mitochondrial membrane potential. The activities of mitochondrial Na^＋ -K^＋ -ATPase and Ca^2＋ -ATPase were detected. The mitochondrial respiratory parameters were recorded with a Clark electrode. The effect of diazoxide on mitochondrial membrane potential and mitochondrial respiration was investigated. Results Compared with the controls, the levels of state 3 （ ST3 ）, respiratory control rate （RCR）, mitochondrial membrane potential content and the activities of mitochondrial ATPase were decreased in the rats that received isoproterenol, while diazoxide pretreatment alleviated the changes of ST3, RCR, mitochondrial membrane potential and the activities of mitochondrial ATPase. Conclusion Preconditioning with diazoxide enhances the activities of mitochondrial ATPase and protects the myocardial mitochondrial function after isoproterenol induced myocardial ischemic injury.

关 键 词：二氮嗪 线粒体 ATP酶 呼吸控制率 膜电位 

分 类 号：R364.12[医药卫生—病理学] R654.202[医药卫生—基础医学]