Apoptosis-inducing Factor In The Rabbit Heart Beating And Arrest Of Different Expression And Significance Of The Content Model Of Cardiopulmonary Bypass

Objective: Myocardial ischemia-reperfusion injury has been the traditionalcardiac arrest cardiopulmonary bypass surgery, a factor of postoperativemyocardial injury.But the beating heart during cardiopulmonary bypass surgeryto maintain intraoperative coronary flow in continuity, in theory, preventmyocardial ischemia-reperfusion injury and reduce myocardial cell injury.Onthe basis of research in molecular biology, beating heart surgery a protectiveeffect on the body, not yet perfect.Myocardial ischemia-reperfusion injury is themost important manifestations can cause apoptosis, which causes apoptosisapoptotic signaling pathways are mainly endogenous mitochondrial pathwaythat way.Mitochondrial pathway can release a number of cytokines,apoptosis-inducing factor (AIF) is one of the important class of pro-apoptoticfactor in the development process of apoptosis, because can lead tonon-caspase-dependent chromatin condensation, which occupies an extremelyimportant position.AIF in cardiopulmonary bypass surgery and cardiopulmonaryarrest beating surgery, whether changes in the expression of certain influence onthe occurrence and development of cardiomyocyte apoptosis, remains to be explored.This experiment rabbit model of cardiopulmonary bypass model, usingreal-time quantitative PCR AIF mRNA expression in cardiomyocytes explorebeating heart surgery under cardiopulmonary bypass in cardiac arrest AIFexpression and cardiopulmonary surgery if there are differences;To investigatethe incidence of myocardial apoptosis mechanisms and effects of major cardiacarrest in surgery.Methods: Rabbit model of cardiopulmonary bypass, the24New Zealandwhite rabbits were randomly divided into2groups (n=12), the experimentalgroup (CPB beating heart group) and control group (CPB cardiac arrestgroup).Experimental group established by the common carotid artery, jugularvein to establish cardiopulmonary bypass, cardioplegia perfusion does not blockthe aorta, a simple extracorporeal120min;The control group after CPB, parallelloop15min, the temperature dropped to28℃-30℃aortic cross-clampingtime, and in the aortic root infusion15-20ml/kg4℃St.Thomas Ⅱcardioplegia.30min and60min at half volume infusion once. After the thirdinfusion begin rewarming,34℃restoring perfusion, the heart resuscitationparallel loop.Stable vital signs stopped after cardiopulmonary bypass.Experimental animals after stopping CPB1hour still alive, deemed theexperiment is successful, the acquisition of myocardial specimens.Methods ofreal-time PCR detection of rabbit cardiomyocytes AIF mRNA expression of twogroups;The use of in situ nick end labeling (TUNEL) assay rabbitcardiomyocytes apoptosis rate.Results:(1) Apoptosis index (AI): the experimental group (4.26±0.62);in the control group (10.09±0.52), myocardial apoptosis index differencewas significant difference (P <0.05).(2) AIF mRNA expression levels of: Experimental group AIF mRNA (expression levels:0.451±0.024) than the control group AIF mRNA(expression level of1.124±0.091) lower (P <0.001).(3)Correlation analysis: the experimental group and the apoptosis rate ofthe group AIF mRNA expression levels of the correlation coefficient was0.679(P <005.), Showed a significant positive correlation; apoptosis rate in thecontrol group and the group of AIF mRNA expression levels correlationcoefficient was0.727(P <0.05), showed a significant positive correlation.Conclusion:(1) Cardiopulmonary bypass surgery, cardiac arrest AIFmRNA expression was higher than beating heart during cardiopulmonary bypasssurgery. AIF involved in apoptosis occurs during cardiopulmonary bypass.(2)Beating heart surgery can reduce apoptosis of myocardial cells,myocardial protection function.