结扎冠状动脉不同分支建立兔心肌梗死模型的效益比较

Effectiveness comparison of myocardial infarction models established by ligating different left coronary branches in rabbits

目的:研究无呼吸机辅助下正中开胸表面结扎兔左冠状动脉不同分支建立心肌梗死模型的成功率、建模效果以及二次开胸存活率。方法:25只兔随机取1只作为健康对照,其余平均分为前降支组和左室支组;两组均行表面结扎冠状动脉建立心肌梗死模型。分别于建模前后行心电图和心脏彩超检查。建模成功后4周末二次开胸,2周后处死动物,留取心脏组织观察病理变化。结果:两组动物建模存活率无差别;以心电图出现ST段动态变化和4周后病理性Q波形成,结合心脏彩超左室缩短分数显著降低(P<0.05)为建模成功标准,左室支组建模的成功率略高于前降支组,但建模成功后的效果两组无明显差别(P>0.05);二次开胸左室支组存活率明显高于前降支组。结论:表面结扎兔冠状动脉左前降支和左室支均能成功建立心肌梗死模型,建模效果无明显差别;结扎左室支时二次开胸存活率明显高于结扎前降支,其更适用于需要多次进行心脏表面操作的实验。

Objective： To investigate the success rates, effects of myocardial infarction models established by ligating different left core- nary branches of rabbits through median thoracotomy without mechanical ventilation assisted, and the survival rates of secondary thora- cotomy. Methods： Twenty five healthy male Japanese white rabbits were subjected. One of them was chosen randomly as the healthy con- trol. The others were randomly separated into two equal groups （n=12）： anterior descending branch group and left ventricle branch group. Myocardial infarction models were established in all the rabbits of both groups. The rabbits in left anterior descending branch group were ligated left anterior descending coronary branch, while the others were ligated the left ventricle coronary branch. Secondary thoracotomy was carried out after successful operation 4 weeks end. Animals were all euthanatized after secondary thoracotomy 2 weeks and histopathological analyses were performed. Results： There was no difference in operation survival rates in the two groups; the success rates in left ventricle branch group were a little higher than that in anterior descending branch group, but the effects after successful oper- ation seemed to be no difference （P〉0.05）; the survival rates of secondary thoracotomy in left ventricle branch group were significantly higher than that in anterior descending branch group. Conclusion： The myocardial infarction model is successfully established by the two methods. The survival rates of secondary thoracotomy by ligating left ventricle branch are much higher than by ligating anterior descend- ing branch, so it＇ s much more suitable for studies in which more than one operation on the surface of infarcted hearts are needed.