BACKGROUND: Ischemia-reperfusion injury in the myocardium after cardiac arrest (CA)and cardiopulmonary resuscitation (CPR) is an important pathologic basis of post-cardiac arrestof syndrome (PCAS), and apoptosi...BACKGROUND: Ischemia-reperfusion injury in the myocardium after cardiac arrest (CA)and cardiopulmonary resuscitation (CPR) is an important pathologic basis of post-cardiac arrestof syndrome (PCAS), and apoptosis is one of the major mechanisms in myocardial ischemiareperfusioninjury. To lessen myocardial ischemia-reperfusion injury after cardiac arrest and CPR,it is important to reduce energy consumption and to increase energy supply in the myocardium.This study aimed to observe changes of cell apoptosis and expression of Bcl-2 and Bax proteinon the myocardium after CPR in rats, and the protective effects of different doses of exogenousphosphocreatine (creatine phosphate, CP) on them.METHODS: A total of 32 male adult Sprague-Dawley rats were randomly divided into 4 groups:control group (group A), CPR group (group B), low-dose CP group (group C, CP 0.5 g/kg at beginning ofCPR and 1.0 g/kg at 2 hours after CPR) and high-dose CP group (group D, CP 1.0 g/kg at beginning ofCPR and 2.0 g/kg at 2 hours after CPR). Cardiac arrest was induced by asphyxiation and CPR startedat 7 minutes after asphyxiation in groups B, C and D. Myocardium samples were taken at 24 hoursafter CPR. Cardiomycytic apoptosis was detected by the TdT-mediated dUTP-biotin nick end labeling(TUNEL) method. The expression of Bcl-2 and Bax protein was measured by immunohistochemistry.RESULTS: Cardiomyocytic apoptosis index (AI) and expression of Bcl-2 and Bax proteinincreased more significantly in groups B, C and D than in group A (P〈0.01), but Bcl-2/Bax ratiosignificantly decreased (P〈0.01). Cardiomyocytic AI and expression of Bcl-2 and Bax proteindecreased more significantly in groups C and D than in group B (P〈0.01), but Bcl-2/Bax ratioincreased more significantly (P〈0.01). Cardiomyocytic AI and expression of Bcl-2 and Bax proteindecreased more signifi cantly in group D than in group C (P〈0.05), but Bcl-2/Bax ratio increased moresignifi cantly (P〈0.05).CONCLUSION: Exogenous phosphocreatine, especially at a large dose, could inhibitcardiomyocytic apoptosis and alleviate myocardial injury after CPR in rats.展开更多
文摘BACKGROUND: Ischemia-reperfusion injury in the myocardium after cardiac arrest (CA)and cardiopulmonary resuscitation (CPR) is an important pathologic basis of post-cardiac arrestof syndrome (PCAS), and apoptosis is one of the major mechanisms in myocardial ischemiareperfusioninjury. To lessen myocardial ischemia-reperfusion injury after cardiac arrest and CPR,it is important to reduce energy consumption and to increase energy supply in the myocardium.This study aimed to observe changes of cell apoptosis and expression of Bcl-2 and Bax proteinon the myocardium after CPR in rats, and the protective effects of different doses of exogenousphosphocreatine (creatine phosphate, CP) on them.METHODS: A total of 32 male adult Sprague-Dawley rats were randomly divided into 4 groups:control group (group A), CPR group (group B), low-dose CP group (group C, CP 0.5 g/kg at beginning ofCPR and 1.0 g/kg at 2 hours after CPR) and high-dose CP group (group D, CP 1.0 g/kg at beginning ofCPR and 2.0 g/kg at 2 hours after CPR). Cardiac arrest was induced by asphyxiation and CPR startedat 7 minutes after asphyxiation in groups B, C and D. Myocardium samples were taken at 24 hoursafter CPR. Cardiomycytic apoptosis was detected by the TdT-mediated dUTP-biotin nick end labeling(TUNEL) method. The expression of Bcl-2 and Bax protein was measured by immunohistochemistry.RESULTS: Cardiomyocytic apoptosis index (AI) and expression of Bcl-2 and Bax proteinincreased more significantly in groups B, C and D than in group A (P〈0.01), but Bcl-2/Bax ratiosignificantly decreased (P〈0.01). Cardiomyocytic AI and expression of Bcl-2 and Bax proteindecreased more significantly in groups C and D than in group B (P〈0.01), but Bcl-2/Bax ratioincreased more significantly (P〈0.01). Cardiomyocytic AI and expression of Bcl-2 and Bax proteindecreased more signifi cantly in group D than in group C (P〈0.05), but Bcl-2/Bax ratio increased moresignifi cantly (P〈0.05).CONCLUSION: Exogenous phosphocreatine, especially at a large dose, could inhibitcardiomyocytic apoptosis and alleviate myocardial injury after CPR in rats.