Effect Of Different Receptors Inhibitors On The Expression Of Calcineurin(CaN) And Myocardium Apoptosis

Part I Effect of the calcineurin(CaN) on the myocardium apoptosis induced by Ischemia-reperfusion and adrenergic receptors in isolated perfused rat heartsObjective To explore the effect of CaN on the cardiomyocyte apoptosis induced by Ischemia-reperfusion and Isoproterenol.Methods To observe changes of the rate of the cardiomyocyte apoptosis and the mRNA level of CaN, a langendorff perfused rats myocardial damage model were built by ischemia reperfusion of varied periods and/or different doses of isoproterenol .And on the basis of myocardial damage,Cyclosporin A, CaN inhibitor was added .The cardiomyocyte apoptosis was judged by TUNEL.The rate of the cardiomyocyte apoptosis was evaluated by flow cytometry and the mRNA level of CaN was investigated by RT-PCR .Results Some doses of Iso caused the apoptosis of cardiomyocytes,and it could promote the rate of cardiomyocyte apoptosis induced by I/R. The mRNA level of CaN was significantly on the rise during the course of the apoptosis induced by I/R and Iso .CsA(Cyclosporin A ),CaN inhibitor , can inhibit dramatically the apoptosis induced by I/R and Iso. Conclusions Isoproterenol can increase the rate of cardiomyocyte apoptosis induced by I/R.Correspondingly, the level of CaN increased. CsA can attenuates the cardiomyocyte apoptosis coacted by I/R and isoproterenol .It suggests that CaN is involved in the cardiomyocyte apoptosis induced by I/R and isoproterenol and has the pro-apoptotic effect. Keywords calcineurin; apoptosis; ischemia/reperfusion; cardiomyocyte; isoproterenolPartⅡEffect of different receptors inhibitors on the expression of calcineurin (CaN) and myocardium apoptosisObjective To explore the influence of different receptors inhibitors on the expression of calcineurin and cardiomyocyte apoptosis induced by Ischemia-reperfusion and Isoproterenol. Methods To observe changes of the rates of the cardiomyocyte apoptosis and the mRNA levels of CaN, a langendorff perfused rats myocardial damage model were built by ischemia-reperfusion and isoproterenol (Iso) 50μM.On the basis of myocardial damage, different receptors inhibitors, atenolol and carvedilol, was added. The cardiomyocyte apoptosis was judged by TUNEL.The rate of the cardiomyocyte apoptosis was evaluated by flow cytometry and the mRNA levels of CaN was investigated by RT-PCR .