The Changes Of Rat Myocardial Cx43, Desmin And CTnT At Different Time Cases After Exhausted Exercise

Objective:To investigate the changes of rat myocardial connexin 43(Cx43), desmin and cardiac troponin T(cTnT)and the rule at different time cases after single bout of exhausted exercises and fourteen consecutive daily exhausted exercises.In order to provide experimental support for the investigation of the mechanism of both exercise-induced heart micro-injuries and myocardial function abnormity.Methods:Male Sprague-Dawley rats were randomly divided into sedentary control group,single bout of exhausted exercise groups and fourteen consecutive daily exhausted exercise groups.Rats were killed at different time cases after exhausted exercise,and use immunofluorescence technic and image-analysis method to study the changes of distribution and content of Cx43,desmin and cTnT in myocardial tissue.Results:1.After single bout of exhausted exercise and consecutive daily exhausted exercises,each time cases myocardial Cx43 distribution pattern had a remarkable change which end-to-end distribution predominating turned to side-to-side distribution predominating.Each time cases after exhausted exercises left ventricle and right ventricle myocardial Cx43 content was remarkable lower than control group(p<0.05). Each time cases after exhausted exercise left ventricle and right ventricle myocardial Cx43 content have not remarkable difference between two diffent exercise form(p＞0.05)2.After single bout of exhausted exercise and consecutive daily exhausted exercises,each time cases myocardial desmin distribution becomed disorder,myocardial fibre striation blur,local myocardial desmin becomed increase or decrease even vanish.Left ventricle myocardial desmin content at oh and 6h after single bout of exhausted exercise was remarkable higher than control group(p＜0.05).Right ventricle myocardial desmin content at 6h after single bout of exhausted exercise was remarkable higher than control group(p＜0.01),right ventricle myocardial desmin content at 24h after exercisewas remarkable lower than control group(p＜0.01).Left ventricle and right ventricle myocardial desmin content was remarkable higher than control group at now after consecutive daily exhausted exercises(p＜0.01).Left ventricle and right ventricle myocardial desmin content at 24h after consecutive daily exhausted exercises was remarkable higher than that at 24h after single bout of exhausted exercise(p＜0.01).3.After single bout of exhausted exercise and consecutive daily exhausted exercises,myocardial cTnT distribution becomed disuniformity which myocardial cTnT becomed increase or decrease even vanish in different section.Right ventricle myocardial cTnT content at 0h,6h and 12h after single bout of exhausted exercise was remarkable higher than control group(p＜0.01).Right ventricle myocardial cTnT content at 6h and 24h after consecutive daily exhausted exercise was remarkable higher than control group(p＜0.05).Right ventricle myocardial cTnT content at now after single bout of exhausted exercise was remarkable higher than that at now after consecutive daily exhausted exercises(p＜0.01).Conclusion:1.The changes of myocardial Cx43 content have not remarkable time cases rule after single bout of exhausted exercise and consecutive daily exhausted exercises.Both exhausted exercise may result in myocardial Cx43 degradation and the change of distribution model,this may be structural base of exercise-induced arrhythmia. 2.The changes of myocardial desmin content after single bout of exhausted exercise have a time cases rule of beginning rise and following fall inside 24 hours,there are similitude rule after consecutive daily exhausted exercises but rise at 24 hour after exercise.Both exhausted exercises may result in the degradation of myocardial desmin and destroy the structure of myocardial cytoskeleton,this may be structural base of myocardial mechanical function abnormity.3.The changes of myocardial desmin content after single bout of exhausted exercise have a time cases rule of beginning rise and following fall inside 24 hours,The changes after consecutive daily o exhausted exercise have a time cases rule of gradual ascend.Both exhausted exercises may make the distribution of myocardial cTnT become disorder,make the distribution becomed disuniformity,this may be one of the reason which result in myocardial mechanical function abnormity.