结扎兔冠状动脉左前降支制作急性心肌梗死模型的价值

目的探讨结扎兔冠状动脉左前降支（LAD）方法制作急性心肌梗死模型的优点及存在的问题。方法26只兔随机分为两组,一组为模型组,一组为假手术组,开胸后,观察兔冠状动脉走行情况,术前及术后0、2、24、48、72 h以针形电极刺入皮下测常规12导联心电图,计算各组胸导联ST段之和（∑ST）,术后72 h处死动物,取出心脏,计算梗死区重量占心室重量百分比,心肌置于甲醛溶液中固定并作病理组织学检查。结果26只兔均具有双侧胸膜,在体及离体观察冠状动脉走行情况,发现左前降支（LAD）长短不一,14只兔LAD位于心室前室间沟的上1/3,8只到达心室前室间沟中1/3,3只到达心尖,1只兔未见LAD。N-BT染色提示：存活的模型组16只兔中,心肌染色较清楚,容易分离测心肌梗死面积者10只,6只动物心肌染色后,染色界限不清晰。存活的模型组16只兔中,10只能显示典型的心电图心肌梗死图形,平均梗死面积10.6%（梗死区重量占全心室重量）;6只兔结扎冠状动脉后,始终未见任何心肌梗死心电图表现,对应的梗死心肌染色面积较小,染色界线不清晰。26只兔中9只术前见到明显ST段电交替现象,术后11只可见明显ST段电交替现象。结论结扎兔LAD方法复制心肌梗死模型,存在不需呼吸机,死亡率低,操作简单等优点,但存在血管变异大,心肌梗死面积小,心肌梗死面积染色不清晰,部分结扎LAD后无心肌梗死心电图表现,结扎前后均存在ST段电交替等缺点。

Some Questions about Making Rabbits AMI Model by Blocking Left Anterior Descending Coronary Artery ~

Objective To study the outcome of making acute myocardial infarction （AMI） animal model by blocking rabbit left anterior descending coronary artery （LAD）. Methods A total of 26 rabbits were divided into two groups, i.e. blocking model group and pseudo operation group. ECG was recorded. The infarct sizes were measured 72 hours later and histopathologic examinations were performed. Results During the operation on the 26 rabbits, pneumothorax occurred in two subjects but they survived. Vantricular fibrillation occurred in two subjects because of blocking LAD. To observe the shape of LAD, we founded that the length o5 LAD was different. LAD was located only in the upper 1/3 of the ventricle in 54 rabbits, and reached to the middle 1/3 between the left and right ventricles in 8 and to cardiac apex in 3 rabbits. There was no LAD in one rabbit. Myocardial dyeing by N-BT was distinct in 10 and not distinct in 6 of the 16 rabbits survived in the blocking model group. Ten rabbits with an average infarct size of 10.6% showed typical dynamic ECG change of AMI and the other 6 rabbits did not. Of the 26 animals, 9 showed ST electrical alternation before operation and 11 after operation. Conclusion The advantage of making AMI model by blocking LAD include that it do not use breathing machine, death rate is low, and that the technique is simple. But it encounters some disadvantage including obvious blood vessel mutation, too small infarct size, and indistinct myocardial dyeing.