【摘要】 目的:探讨离体小鼠心脏缺血后适应模型建立的可行性以及对梗死心肌面积、再灌注心律失常及冠状动脉灌流量的影响。方法:将45只国产成年KM小鼠随机分为缺血后适应组、缺血再灌注组、空白对照组3组,每组15只。小鼠开胸心脏离体后,迅速将主动脉弓连接到Langendorff离体心脏灌注系统进行逆行灌流。各组均进行稳定灌流10min,缺血后适应组停止灌流30min,造成急性全心缺血,在完全再灌注早期给予反复短暂灌流/停止灌流的后适应,之后持续灌注120min;缺血再灌注组为同期离体完成缺血30min再灌注120min,在停止灌流前后不做任何特殊处理;空白对照组持续离体灌流,不加任何干预。采用三苯基氯化四氮唑染色的方法确定梗死心肌面积,并同步记录全程心电图,收集灌流液,测定冠状动脉灌流量。结果:缺血后适应组再灌注120min心肌梗死范围为(26.1±2.7)%,较对照组的(42.1±3.3)%明显减少(P<0.05);缺血后适应组心律失常积分为(10.2±2.5),较缺血再灌注组(12.2±1.7)低,但差异无统计学意义(P>0.05);再灌注后120min2组间冠脉血流量无明显差别。结论:离体小鼠心脏缺血后适应模型的技术稳定可靠,后适应能有效地降低灌注缺血/再灌注损伤,明显地减少心肌梗死范围,同时再灌注心律失常的发生率也有所降低。更多还原

【Abstract】 Objective: To explore the possibility of a mouse model of ischemic postconditioning in Langendorff perfused heart and investigate the effect on myocardial infarction area, reperfusion arrhythmia injury and coronary flow of cardiac ischemic postconditioning in isolated heart. Methods: Forty five adult KM mice were randomly divided into three different groups: ischemia postconditioning group,ischemia-reperfusion group and control group, 15 mice in each group. Each mice undergone open-chest surgery,the hearts were removed and immediately canuulated and retrogradationly perfused in Langendorff apparatus. All the hearts were stabilized for 10 min and then received 30 min ischemia and 120 min reperfusion, 3 cycles of 10 s reperfusion followed by 10 s arrest of perfusion were applied during the early minutes of reperfusion in postconditioning group. I/R group hearts had no episodes of postconditioning after reperfusion, control group hearts only received perfusion and had no ischemia. At the end of I/R, the infarct size was determined by TTC staining, the ECG were recorded and the volumes of coronary were caculated during the whole procedure. Results: Following 120 min reperfusion, infarct size was significantly reduced in postconditioning group (26.1±2.71)% compared with I/R group hearts (42.1±3.32)%, (P<0. 05), arrhythmia scores decreased in postcondioning group (10.2±2.5) with no significant difference compared with I/R group hearts (12.2±1.7)%, (P>0.05) and no significant difference in post ischemic coronary flow (P>0.05). Conclusions: It is possible in establishment of postconditioning in Langendorff perfused mouse heart. Postconditioning plays a pivotal role in reducing myocardial infarct size after ischemia/ reperfusion injury. Ichemia postconditioning at onset of reperfusion obviously can reduce myocardial infarct size, meanwhile, the occurrence of arrhythmias after I/R injury in mouse can be reduced by postconditioning.更多还原