论文部分内容阅读
目的对结扎不同冠脉分支制备兔急性心肌梗死模型的方法进行对比研究,并探讨其在科研应用中的意义。方法选择30只新西兰大白兔,随机分为2组,非人工通气状态下,分别结扎左前降支(left anterior descending,LAD)及左旋支的粗大恒定分支左室支(left ventricular branch,LVB),并于结扎前及结扎后30 min、24 h、1周行心电图及心肌酶检测,结扎前及结扎后24 h、1周经静脉行心肌超声造影(myocardial contrast echocardiography,MCE)检查,结扎后1周行冠脉造影及血液动力学指标检测,随即处死动物留取左室标本称重并进行氯化三苯四氮唑(TTC)染色测定梗死面积。结果①冠脉结扎术后30 min两组心电图ST均明显抬高,24 h后LAD组即明显回落(P<0.05),1周后差异更为明显(P<0.01)。②术后1周冠脉造影证实LAD组81.8%近中段闭塞,LVB组100%近中段闭塞,差异无统计学意义(P>0.05)。③造模1周后两组收缩压(systolic blood pressure,SBP)、舒张压(diastolic blood pressure,DBP)、左心室压力最大上升和下降速率(maximumrate of rise and descend of left ventricular pressure,±dp/dt max)、左室舒张末压(left ventricular end-diastolic pressure,LVEDP)、射血分数(ejection factor,EF)均较术前明显减低(P<0.05),左心室舒张末期内径(left ventricular end-diastolic dimension,LVEDD)较术前增大,LVB组较LAD组变化更为明显(P<0.05),尤以A×β最为显著(P<0.01)。④TTC染色后计算LAD组心梗面积小于LVB组(P<0.05),且心梗前后心肌灌注指标A×β变化值与±dp/dt max、心梗面积呈显著正相关(r=0.62、0.55、0.80,P<0.05)。结论结扎LVB建立的兔急性心肌梗死模型梗死面积理想,范围稳定可靠,可用于长期随访观察的急性心肌梗死相关研究,而结扎LAD则更适用于急性再灌注或侧支循环实验观察。
Objective To compare the methods of ligating different branches of coronary artery in the preparation of acute myocardial infarction model in rabbits and to explore its significance in the application of scientific research. Methods Thirty New Zealand white rabbits were randomly divided into 2 groups. Under non-artificial ventilation, left anterior descending (LAD) and left ventricular branch (LVB) Electrocardiogram (ECG) and myocardial enzymes were detected before ligation and at 30 min, 24 h, and 1 week after ligation, and myocardial contrast echocardiography (MCE) was performed before and at 24 h and 1 week after ligation. Peripheral coronary angiography and hemodynamic tests were performed. Immediately after sacrifice, left ventricular specimens were weighed and infarcted area was determined by TTC staining. Results ① The electrocardiogram ST of the two groups were significantly elevated at 30 min after coronary ligation, and the levels of LAD decreased significantly after 24 h (P <0.05). The difference was more obvious after 1 week (P <0.01). ② Coronary angiography at 1 week after operation confirmed 81.8% occlusion in the LAD group and 100% occlusion in the LVB group, with no significant difference (P> 0.05). ③ After 1 week of modeling, the systolic blood pressure (SBP), diastolic blood pressure (DBP), maximumrate of rise and descend of left ventricular pressure (± dp / dt max, left ventricular end-diastolic pressure (LVEDP) and ejection fraction (EF) were significantly lower than those before operation (P <0.05), left ventricular end-diastolic -diastolic dimension (LVEDD) increased compared with that before operation. LVB group was more obvious than LAD group (P <0.05), especially A × β (P <0.01). ④TTC staining showed that the area of myocardial infarction in LAD group was smaller than that in LVB group (P <0.05), and the value of A × β in myocardial perfusion index before and after myocardial infarction was positively correlated with ± dp / dt max and myocardial infarction area (r = 0.62,0.55 , 0.80, P <0.05). Conclusions The infarct size of acute myocardial infarction model established by ligation of LVB in rabbit model is ideal and its range is stable and reliable. It can be used in long-term follow-up study of acute myocardial infarction. Ligation of LAD is more suitable for acute reperfusion or collateral circulation experiment.