力竭运动后不同时相大鼠心肌CnAβ的变化

The Change in Rat Myocardial CnAβ at Different Time Courses after Exhausted Exercise

目的:探讨力竭运动后不同时相大鼠心肌CnAβ表达的变化特点。方法:90只健康成年雄性SD大鼠,分为一次力竭游泳运动组(n=40)、2周反复力竭游泳运动组(n=40)及安静对照组(n=10),两运动组根据取材时间不同又分别分为力竭运动后0、6、12及24小时组(n=10)。应用免疫荧光技术和免疫印迹法检测大鼠心肌CnAβ含量。结果:免疫荧光检测结果显示一次性力竭运动各组大鼠心肌CnAβ灰度值与对照组相比均无显著性差异(P>0.05);而反复力竭运动各组大鼠心肌CnAβ灰度值均高于对照组,其中运动后即刻组显著高于对照组(P<0.05)。免疫印迹法检测两种不同力竭运动后心肌CnAβ的积分灰度值比值变化趋势与免疫荧光法检测心肌CnAβ灰度值变化基本一致。结果提示,反复力竭运动大鼠心肌CnAβ蛋白含量的升高可能与运动性心肌微损伤发生有关。

Objective To investigate the change in the content of CnAβ in rat myocardial tissue at different time courses after exhausted exercise. Methods Ninety male Sprague-Dawley rats were divided into sedentary control group （n=10）,single bout of exhausted exercise group（n=40）and 14-day repeatedly exhausted exercise group（n=40）. Rats were killed at 0,6,12 and 24 hours after the last exercise. Immunofluorescence and Western blotting were used to detect the changes in the content of CnAβ in rat myocardium. Results （1） There was no significant difference in content of CnAβ in rat myocardial tissue after single bout of exhausted exercise comparing to the control group （P 〉 0.05）,while the content of CnAβ in rat myocardial tissue at 0h after 14-day repeatedly exhausted exercise was remarkably higher than that in control group （P 〈0.05）. The changing trend of CnAβ in rat myocardium at different time courses after exhausted exercise was almost the same either using Western blot or immunofluorescence. Conclusion Increased CnAβ in rat myocardium after repeatedly exhausted exercise could be related to the exercise-induced heart micro-injury.