力竭运动后不同时相大鼠心肌核呼吸因子1的变化

The Changes of Rat Myocardial NRF-1 at Different Time Cases after Exhausted Exercise

目的:探讨力竭运动后不同时相心肌核呼吸因子1(NRF-1)的变化特点。方法:90只健康成年雄性SD大鼠,分为一次力竭游泳运动组、2周反复力竭游泳运动组及安静对照组,分别于力竭运动后即刻、6、12及24小时取材,应用免疫荧光组化技术和图像分析方法研究大鼠心肌NRF-1蛋白含量的变化。结果:一次力竭游泳运动后即刻组大鼠心脏各部位(左心室、室间隔、右心室)中NRF-1蛋白含量均显著低于对照组(P<0.05),同时即刻组左心室NRF-1蛋白含量显著低于其他各组(P<0.05),即刻组和12小时组室间隔NRF-1蛋白表达均达到最低值,而24小时组右心室NRF-1蛋白含量显著低于对照组(P<0.01);反复力竭运动后6小时组和24小时组,大鼠心脏各部位蛋白含量显著低于对照组(P<0.05),力竭后24小时组与对照组相比具有显著性差异(P<0.05)。结论:一次力竭运动和反复力竭运动可导致大鼠NRF-1蛋白表达明显降低,力竭运动后12小时室间隔NRF-1蛋白含量显著低于其他各部位,这可能是运动性心肌微损伤和心律失常发生的重要机制之一。

Objective To investigate the changes of the myocardial tissue at different time cases after exhausted content of nuclear respiratory factor-1 （NRF-1） in rat exercise. Methods Ninety male Sprague-Dawley rats were divided into sedentary control group, single bout of exhausted exercise groups and 2-week consecutive daily exhausted exercise groups. Rats were killed at 0,6,12 and 24 hours after exhausted exercise. Immuno-fluorescence histochemistry and image-analysis method were used to study the changes of the content of myocardial NRF-1 in rats. Results Myocardial NRF-1 protein content of each part of the heart （left ventricle, interventricular septum,and right ventricle） immediately after exhaustive swimming were significantly lower than the control group （P〈0.05）, while NRF-1 protein content of left ventricular in 0-hour group was significantly lower than the other groups （P〈0.05） ; NRF-1 protein content of interventricular septum in 0-hour group and 12-hour group reached the minimum value, and NRF-1 protein content changes of right ventricle in the 24-hour group was significantly lower than the control group （P%0.01）; For 6-hour and 24-hour group after exhaustive exercise group, the protein content in all heart parts were significantly lower than the control group （P〈0.05）,exhausted after a 24-hour group compared with the control group was significant （P〈0. 05）. Conclusion The content of NRF-1 expression was decreased after exhausted exercises.