外源性磷酸肌酸预处理对大鼠心肌缺血-再灌注损伤的保护作用

摘要

Objective To study the protective effects of creatine phosphate pretreatment on myocardial ischemia-reperfusion (I-R) injury in rats. Methods Thirty adult male SD rats were randomly and equally divided into three groups of S (sham operated), I-R(ischemia for 30 min and reperfusion for 120 min) and CP(creatine phosphate 10 ml/kg intraperitoneally injected 30 min before ischemia). Myocardial tissues were tested for adenosine triphosphate(ATP) and superoxide dismutase (SOD) activity in the myocardium were examined. Myocardial ultrastructure and mitochondria swelling were observed under light and electron microscope. Results ATP level and SOD activity were higher in group CP than those in group I-R[(2.76±0.98)μmol/mg vs. (1.65±0.84) μmol/mg,(42.47±2.16) U/mg vs. (49.56±3.28) U/mg](P＜0.05). Compared to group I-R, the changes of myocardial ultrastructure and mitochondria in group CP were slighter. Conclusion The creatine phosphate pretreatment has the protective effects on the myocardium against I-R injury in rats.%目的 研究外源性磷酸肌酸(CP)预处理对大鼠心肌缺血-再灌注(I-R)损伤的保护作用.方法 健康雄性SD大鼠30只,随机均分为三组:假手术(S)组、I-R组和CP预处理组(CP组).I-R、CP预处理组结扎冠状动脉左前降支30 min,再灌注120 min制备心肌I-R损伤模型.缺血前30 min,CP组经腹腔注射CP 10 ml/kg.于再灌注120 min时处死大鼠,测定心肌三磷酸腺苷(ATP)含量和超氧化物岐化酶(SOD)活性,光学显微镜和透射电镜下观察心肌组织结构变化及线粒体水肿情况.结果 CP组心肌组织中ATP含量、SOD活性显著高于I-R组[(2.76±0.98)μmol/mg vs.(1.65±0.84) μmol/mg、(42.47±2.16) U/mg vs.(49.56±3.28) U/mg] (P<0.05).I-R组心肌组织明显水肿、出血和坏死;CP组心肌组织结构及线粒体变化较I-R组明显减轻.结论 外源性CP对大鼠心肌I-R损伤具有明显保护作用.