磷酸肌酸对大鼠心肺复苏后心肌细胞凋亡的影响

目的 通过观察大鼠心肺复苏(CPR)后心肌细胞凋亡及凋亡相关蛋白Bax,Bcl-2的表达及外源性磷酸肌酸(CP)干预的影响,研究大鼠CPR后心肌损伤机制及外源性CP的保护作用.方法 将32只成年雄性SD大鼠随机分为对照组(A组)、常规复苏组(B组)、常规剂量CP组(C组,胸外按压时首次给药CP 0.5g/kg,2 h后再次给药1.0g/kg)、大剂量CP组(D组,胸外按压时首次给药CP 1.0g/kg,2 h后再次给药2.0g/kg).每组动物8只.建立窒息型大鼠心搏骤停(CA)-CPR模型,ROSC后24 h取心肌标本待测.以脱氧核糖核昔酸末端转移酶介导的缺口末端标记法(TUNEL)检测ROSC后24h的心肌细胞凋亡指数(AI);以免疫组化法检测ROSC后24h的心肌细胞Bcl-2,Bax蛋白表达.数据比较采用方差分析.结果 与A组比较,CPR后24h B,C,D各组心肌凋亡指数及Bax,Bcl-2蛋白表达均显著升高(均P＜0.01),Bcl-2/Bax值均明显降低(P＜0.01);与B组比较,C组和D组心肌的凋亡指数及Bax,Bcl-2蛋白表达均明显降低,Bcl-2/Bax值均明显上升(P＜0.01);与C组比较,D组的凋亡指数及Bax,Bcl-2蛋白表达均明显降低,Bcl-2/Bax值明显上升(P＜0.05).结论 外源性磷酸肌酸可明显抑制窒息型大鼠CPR后心肌细胞凋亡,对心肺复苏后心肌损伤具有保护作用,该作用以大剂量时更明显.

Effect of exogenous phosphocreatine on cardiomycytic apoptosis and expression of Bcl-2 and Bax after cardiopulmonary resuscitation in rats

Objective To observe the changes of cell apoptosis and levels of Bcl-2 and Bax protein in myocardium after cardiopulmonary resuscitation (CPR) in rats and to study the protective effects of different doses of exogenous phosphocreatine (creatine phosphate, CP) on cell apoptosis. Methods A total of 32 male adult SD rats were randomly divided into 4 groups, namely control group ( group A), CPR group (group B), low dose CP group (group C, phosphocreatine 0. 5 g/kg given at beginning of CPR and 1.0 g/ kg 2 hour after CPR) and high dose CP group ( group D, phosphocreatine 1.0 g/kg at beginning of CPR and 2. 0 g/kg 2 hours after CPR) . Cardiac arrest was induced by asphyxiation and CPR was started 7 min after asphyxiation it groups B, C and D. Myocardium samples were taken 24 hours after CPR for detecting myocardium cell apoptosis by TUNEL method. The levels of Bcl-2 and Bax protein were measured by using immunohistochemistry. Experimental data were processed with variance analysis in SPSS package. Results Compared with group A, myocardium cell apoptosis index (AI), and the levels of Bcl-2 and Bax proteinincreased significantly in groups B, C and D (P ＜0. 01 ), and Bcl-2/Bax ratio decreased significantly (P ＜0. 01 ) . Compared with group B, myocardium cell AI and levels of Bcl-2 and Bax protein decreased significantly in groups C and D ( P ＜ 0. 01 ), and Bcl-2/Bax ratio increased significantly ( P ＜ 0. 01 ) .Compared with group C, myocardium cell AI and levels of Bcl-2 and Bax decreased significantly in group D (P ＜ 0. 05 ), and Bcl-2/Bax ratio increased significantly ( P ＜ 0. 05 ) . Conclusion Exogenous phosphocreatine, especially inlarge dose, could inhibit apoptosis of myocardium cells and alleviate myocardium injury after CPR in rats.