不同力竭运动后大鼠心脏传导系统肌钙蛋白T mRNA和蛋白的变化及其在运动性心律失常发生中的作用  

The expression of troponin T in cardiac conduction system after exhaustive exercise and their role in exercise induced arrhythmia

作　　者：常芸[1] 杨红霞[1] 

机构地区：[1]国家体育总局科研所运动健康研究中心,北京100061

出　　处：《中华临床医师杂志（电子版）》2012年第16期4748-4753,共6页Chinese Journal of Clinicians(Electronic Edition)

基　　金：国家体育总局体育科学研究所基本科研业务经费(09-10)

摘　　要：目的探讨力竭运动后不同时相心脏窦房结、房室结和浦肯野氏纤维细胞骨架因子肌钙蛋白T(cTnT)基因和蛋白水平的表达特点,为运动性心律失常发生机制的阐明提供实验依据。方法 100只健康成年雄性SD大鼠随机分为一次力竭运动、反复力竭组及相应的其对照组,每组10只。分别于力竭运动后0、4、12及24h应用激光显微切割技术定位并收集窦房结、房室结和浦肯野氏纤维细胞团,进行免疫荧光组织化学及实时荧光定量PCR分析cTnT的mRNA和蛋白表达变化。结果一次力竭运动后,窦房结cTnT mR-NA和蛋白表达变化不大,各时相组间无显著性差异;房室结cTnT mRNA和蛋白表达在运动后12h显著高于对照组(P<0.01),浦肯野纤维cTnT mRNA和蛋白表达呈逐渐升高趋势,在运动后24h显著高于对照组(P<0.01)。反复力竭运动后窦房结、房室结和浦肯野纤维cTnT mRNA和蛋白表达呈先升高后下降的趋势,在运动后即刻显著高于对照组(P<0.05)。结论力竭运动后心脏传导系统各部位细胞骨架支撑因子cTnT在mRNA和蛋白水平呈异常高表达提示心脏传导系统细胞骨架结构损伤,可能构成运动性心律失常的病理基础。Objective This paper discusses on the mRNA and protein expression of troponin T on cardiac sinus node,atrioventricular node and Purkinje fibers at different time phrase after exhaustive exercise,and trys to provide experimental evidence for clarifying the mechanism of exercise-induced arrhythmia.Methods 100 healthy adult male SD rats were grouped into the one-time exhaustive swimming group(n=40),the 2-week repeated exhaustive swimming group(n=40),and 2 control groups(10 rats for each group).The exercise rats were sacrificed at 0,4,12,and 24 hours after exhaustive swimming,the control groups were sacrificed at the same time with the 0 hour after exhaustive swimming group.The cells of SAN,AVN and Purkinje′s fiber were spotted and collected in the approach of Laser Micro dissection(LMD).The mRNA and protein expression of troponin T on the SAN,AVN and Purkinje′s fiber were analyzed by real-time fluorescent quantitative PCR,immunochemistry and image analysis.Results After one-time exhaustive exercise,the expression of mRNA and protein of troponin T on cardiac sinoatrial node has no significant changes at different time-phrase;the expression of mRNA and protein of troponin T on atrioventricular node increased greatly at 12 hours compared to control group(P<0.01);the expression of mRNA and protein of troponin T on Purkinje fiber increased markedly at 24 hours as compared with control group(P<0.01).The expression of mRNA and protein of troponin T on cardiac conduction system increased greatly immediately after repeated exhaustive exercise as compared with control group(P<0.05).Conclusions The abnormal high expression of mRNA and protein of troponin T after exhaustive exercise shows that there are the cytoskeleton cell damage in cardiac conduction system.Those changes might be the pathology basis of the exercise induced arrhythmia.

关 键 词：肌钙蛋白T 窦房结 房室结 浦肯野纤维 力竭运动 

分 类 号：R87[医药卫生—运动医学]