【摘要】 目的:观察力竭运动后大鼠心肌肌钙蛋白I(cTnI)、肌红蛋白(Mb)基因和血清cTnI、Mb水平变化,探讨运动性心肌微损伤的早期、特异性诊断指标与诊断方法。方法:80只SD大鼠,采用一次力竭游泳运动和2周反复力竭游泳运动建立运动性心肌微损伤大鼠动物模型,测定力竭运动后不同时相(4、12及24小时)血清cTnI和Mb含量及心肌cTnI、Mb mRNA表达。结果:(1)一次性力竭运动后各时相大鼠血清cTnI含量与对照组相比无显著性差异;运动后血清Mb含量显著升高,12~24小时恢复。(2)反复力竭运动后大鼠血清cTnI显著升高,运动后24小时仍未回落;血清Mb与对照组相比无显著性差异。(3)一次和反复力竭游泳运动后,大鼠心房肌和心室肌cTnI和Mb mRNA表达均呈下降趋势,其中心房肌cTnI、Mb mRNA表达的下降趋势较心室肌明显。结论:(1)力竭运动后,血清Mb升高早、持续时间短;cTnI升高较晚,特异性强、持续时间长,联合检测血清cTnI和Mb有助于运动性心肌微损伤的早期、特异性诊断。(2)心房肌和心室肌cTnI基因、心房肌Mb基因在转录水平均以下调方式参与运动性心肌微损伤调控。(3)心房肌cTnI和Mb基因显著下调是心房易损伤的机制之一。更多还原

【Abstract】 Objective To investigate gene and protein expression of cTnI and Mb in myocardium and serum of rats at different time courses after exhausted exercise for seeking the earlier,specific and sensitive indexes and method in detecting exercise-induced minor myocardial damage(EIMD). Methods The model of exercise-induced mi-nor myocardial injury was established through single bout of exhaustive swimming and 2-week successive exhaustive swimming. The rats were killed at 4h,12h and 24h after the last exhaustive swimming. The cTnI and Mb in serum and myocardial mRNA of cTnI and Mb gene were detected. Results (1)In single bout of exhaustive swimming,the level of serum Mb was significantly higher than that in control group,and recovered after 12~24h; There was no dif-ference in cTnI as compared with that in control group. (2)The level of serum cTnI was significantly higher in the group of 2-week successive exhaustive exercise than that in control group,and was not able to recover after 24h after exercise. There was no difference in serum Mb level as compared with that in control group.(3)The expressions of both cTnI and Mb gene mRNA in atrium and ventricle after single bout of exhaustive swimming and 2-week succes-sive exhaustive swimming decreased,especially in atrium. Conclusion(1)After exhaustive swimming,Mb increased earlier with shorter persistence time than cTnI in serum,and cTnI revealed higher specificity and sensitivity in detect-ing EIMD.(2)cTnI gene in atrium and ventricle and Mb gene in atrium was down-regulated in exercise induced car-diac injury.(3)The change in cTnI and Mb gene expression in atrium probably was one of the causes of exercise in-duced atrial injury.更多还原