Effects Of Coronary Sinus Occlusion To The Cardiac Troponin â…  (cTnI) And The Fibronectin (Fn) In Healthy Dogs

BackgroundThe research of coronary vein attracts more and more attention,with the clinical application of the radio frequency ablation and the cardiac resynchronization therapy,. Coronary sinus is one of the most important constitute landmarks of the coronary venous system, and coronary sinus is one of the most important gateways for the final collection of venous drainage of the heart (mainly from left ventricle). Whether or not that the same pathological changes will take place in the cardiac venous system as other in the venous, such as venous thrombosis, thrombophlebitis, varicose veins, and stenosis? and if these will affect the cardiac structure and function?ObjectiveIn this experiment, coronary sinus occlusion in healthy dogs is used to establish animal model of intermittent coronary sinus occlusion in order to study its effects on the cardiac troponinⅠ(cTnⅠ) and the Fibronectin (Fn)and finally provides a new way of thinking for diagnosis and treatment of heart diseases which were related to the coronary vein system in the future. Methods18 healthy dogs was grouped into the control,the block 1 hour,the block 2 hours randomly. All dogs received chest open operation.Scatheless slide wire was used to ligate coronary vein sinus at where nearest the orifce of coronary vein sinus from epicardium. We detected the variation of cardiac troponinⅠ(cTnⅠ) and Fibronectin(Fn) in plasma before and 2h after the experiment in the three groups. Respectively kill animals after an hour or two hours. In the contrast group, coronary vein sinus was not ligated. then their hearts was taken out to select the same based of Left ventricle.The immunohistochemical method(the three-step)was used to detect the expression of protein cTnⅠand Fn in the autopsiedhearts of the control,the block 1 hour,the block 2 hours in 18 cases respectively. The samples were also subjected to Hematoxylin-eosin staining(HE).Results1 The changes of the cardiac troponinⅠ(cTnⅠ) and the Fibronectin (Fn) were not obvious after Coronary sinus obstruction.2 The changes to cardial by coronary sinus obstruction were atrophy of Myocardium and myocardial interstitiual edema,hyperemia and hemorrhage in interstistial vascular were observed from optical microscope.3 The expression of the cardiac troponinⅠ(cTnⅠ) and the Fibronectin (Fn) after coronary sinus obstruction were that (1) The average light density of cTnⅠin the block 2 hours, the block 1 hour and the control were 0.021327±0.0013; 0.046435±0.0047;0.082121±0.0016 respectively, in per 200x high power field. There were significant difference among the three groups(P<0.001),there was also signific difference between the block 1hour and the block 2 hours(P<0.001). The cTnⅠdeficiency was in the experiment groups. (2) The average light density of Fn in the block 2 hours,the block 1 hour and the control were 0.084020±0.0027; 0.070347±0.0028 and 0.042883±0.0041 respectively in per 200x high power field. There were significant difference among the three groups (P<0.001),there was also signific difference between the block 1hour and the block 2 hours(P<0.001). The expression of the Fn was strengthener in the experiment groups.Conclusion(1) The cardiac troponin I (cTnⅠ) and the Fibronectin (Fn) of changes were not obvious after Coronary sinus obstruction 1 hour or 2 hours.(2) The changes to cardial by coronary sinus obstruction 1 hour or 2 hour were edema of Myocardium and myocardial interstitiual edema, hyperemia and hemorrhage in interstistial vascular were observed from optical microscope.(3) Coronary vein sinus occlusion 1 hour or 2 hour caused myocardial injury, The expression of the Fn was strengthener,but, cTnⅠwas deficiency.(4) The study of coronary vein occlusion may provide a new way of thinking for diagnosis and treatment of heart diseases which were related to the coronary vein system in the future.