A Convenient Mouse Model of Myocardial Infarction for Developing Countries

Abstract

Purpose Myocardial infarction (MI) mouse model is an important tool in the experimental study of ischemic heart disease. However, this model has not been in common use in developing countries because of the high experiments cost and sophisticated surgical skills. The purpose of this study was to introduce a convenient protocol to create a MI model in mice. Methods The C57BL/6 J (wild type) male mice (n = 60, 8 weeks old) were used and divided into 2 groups: the first 30 consecutive mice in early phase of this study (Early group) and the remaining 30 mice (Late group). Mice were anesthetized with pentobarbital sodium (50 mg/kg) and performed endotracheal intubation. During mechanical ventilation, a left lateral thoracotomy was made and the left anterior descending coronary artery was ligated. After the chest was closed, mice were weaned from mechanical ventilation and extubated. After 28 days of operation, echocardiography was performed. Non-infarction mice were used as control. Results Twenty-eight-day survival rate was 46.7% in the Early group and 83.3% in the Late group (p < 0.05). The causes of death were heart failure, heart damage, lung injury and endotracheal intubation failure. Left ventricular ejection fraction was significantly lower in the MI mice compared with the control (32.2% vs. 47.2%, p < 0.05), and also lower in the Late group compared with the Early group (29.3% vs. 38.3%, p < 0.05). Conclusions Sophisticated skill was needed to create MI mice. All surgeries were carried out by a same beginner researcher; however, this report on our 60 consecutive MI mice revealed a significant improvement in survival rate during the first 30 cases. Ejection fraction was significantly lower in the Late group, which means that we could make larger MI area in the Late group. Our present protocol may provide researchers in Viet Nam with useful experimental information.