Establishment of a Rabbit Model of Acute Myocardial Infarction by Coronary Artery Catheterization

Objective To establish a rabbit model of acute myocardial infarction by coronary artery catheterization.Methods Twenty male New Zealand rabbits were used in this study.Coronary arteriography was performed at first and then a microcatheter was put into the distal segment of left anterior descending(LAD) coronary artery.The obstructive glue was prepared by mixing macromolecular embolic agent with iodized oil,and it was pushed into the vessel via the microzatheter to induce acute myocardial infarction.The changes of electrocardiogram were recorded after preoperative preparation, operation and 1 week later.Myocardium samples were prepared by hematoxylin-eosin(HE),nitroblue tetrazolium(NBT),and immunohistochemical staining at the end of experiment.Results 16 rabbits survived among the 20 operated animals.Coronary angiography displayed that the obstructive glue detained continuously in the distal segment of LAD inducing a complete occlusion.The dynamic ECG changes showed ST segment elevation and development of abnormal Q waves.The gross appearance of heart showed that the infarction area was at the antero-lateral wall of left ventricle and presented off-white color.HE staining showed fibrosis,scar formation and calcification in the infarction area,and myocardial degeneration and inflammatory cell infiltration in the ischemic area.All these were accorded with typical pathological changes of myocardial infarction.The infarction area was 28.32%±5.21%,determined by NBT staining.Immunohistochemical staining showed that the CD34 positive area and the density of neovasculature in the ischemic area were significantly higher than that in infarction or normal area(P0.05).Conclusion A rabbit model of acute myocardial infarction has been successfully established by an interventional procedure using coronary artery catheterization.It can avoid the adverse effects of open-chest operation,and the induced changes are more consistent with the pathological featuress of human acute myocardial infarction.