左卡尼汀联合比索洛尔对内质网应激介导的心肺复苏后大鼠心肌损伤的影响

Effects of L-carnitine and bisoprolol on endoplasmic reticulum stress-mediated myocardial injury after cardiopulmonary resuscitation in rats

目的 探讨左卡尼汀联合比索洛尔治疗对内质网应激介导的心肺复苏后大鼠心肌损伤的影响.方法 空白对照组为假手术组（SHAM组）,电生理刺激建立心肺复苏模型（CR组）,心肺复苏模型建立后给予注射左卡尼汀组（L组）,比索洛尔治疗（B组）,以及联合用药组（LB组）.复苏成功后24 h后HE染色检测心肌损伤指标,缺口末端标记法（TUNEL）法检测心肌细胞凋亡情况、免疫印迹检测内质网应激关键因子GRP78等蛋白的表达.结果 与SHAM组相比,其余4组均发生心肌病理损伤,心肌细胞凋亡率明显升高[（32.5％±3.8％）、（52.1％±4.2％）、（47.1％±5.8％）、（42.1％±4.6％）比（0.4％±0.0％）]（P＜0.05）,内质网关键因子蛋白表达升高（P＜0.05）;LB以及B组内质网因子蛋白表达下降,心肌损伤程度较CR组减轻,其中LB组最明显,LB组凋亡指数（32.5％±3.8％）,（P＜0.05）;结论 左卡尼汀联合比索洛尔可以通过抑制心肌内质网应激反应,减轻心肺复苏后的心肌损伤.

Objective To explore the effects of L-carnitine and bisoprolol on endoplasmic reticulum stress-mediated myocardial injury after cardiopulmonary resuscitation in rats.Methods A total of 75 Sprague-Dawley rats were randomly divided into 5 groups of sham operation （sham）;cardiopulmonary resuscitation （CR）,L-carnitine （L）,bisoprolol treatment （B） and L-carnitine and bisoprolol treatment （LB）.Myocardial pathological changes were detected by hematoxylin and eosin,myocardial apoptosis by terminal deoxynucleotidyl transferase mediated dUTP nick and the expressions of key factors in endoplasmic reticulum （ER） by Western blot.Results Compared with sham group,apoptosis and pathological lesions significantly increased in other groups （P 〈 0.05）.And the levels of GRP78,CHOP and Caspase-12 were significantly higher （P 〈 0.05）.The expression of ER factor protein and the degrees of myocardial injury in LB and B groups decreased compared with CR group.And LB group was the most obvious.Conclusions Combined use of levocarnitine and bisoprolol exerts protective effects on cardiopulmonary resuscitation in rats.And the mechanism may be related to an inhibition of ER stress.