小鼠心梗模型的建立与无创评价

目的建立小鼠的心肌梗死模型,提高动物存活率,并使用心脏超声进行无创心功能评价。方法昆明雄性小鼠20只,气管插管后由左侧第4肋间进胸,结扎冠状动脉左前降支建立小鼠心肌梗死模型,在模型建立的前1 d和术后1 d、1周分别使用心脏超声检测左室收缩末直径、舒张末直径、缩短分数和射血分数,并于术后第8天进行病理检查。结果小鼠心肌梗死模型建立过程中早期死亡率10%（2/20）,术后1周内死亡率15%（3/20）,经过超声评价,造模成功率为75%（15/20）。小鼠心功能明显下降,射血分数由手术前的（92.1±3.45）%下降到术后1周的（49.8±14.20）%,缩短分数由手术前的（61.4±2.85）%下降到（26.1±9.01）%;心室明显扩大,左室收缩末直径由（13.9±1.98）μm扩大到（36.5±7.37）μm,舒张末直径由（35.9±3.12）μm扩大到（48.9±6.05）μm。病理学检查见明显瘢痕形成。结论通过结扎冠状动脉左前降支的方法建立了小鼠心肌梗死模型并可以使用超声心动图评价这一模型。

Establishment and Non-Invasive Assessment of a Mouse Model of Myocardial Infarction

Objective To establish a standardized mouse myocardial infarction model with a high survival rate,and non-invasively evaluate its cardiac function by echocardiography.Methods A total of 20 Kunming male mice were enrolled into this study.The left anterior descending coronary artery was ligated through the left fourth intercostal space after intubation.The echocardiographic assessment of myocardial infarction and heart function was performed 1 day preoperatively,1 day and 1 week postoperatively.Pathological examination was performed 8 days postoperatively.The ejection fraction（EF）,shortening fraction（FS）,end systolic dimension（ESD）,and end diastolic dimension（EDD） were recorded and analyzed.Results The acute and one-week mortality rates were 10%（2 /20） and 15%（3 /20）,respectively.The echocardiography showed that the success rate of establishment of the infarction model was 75%（15 /20）.The heart function of the mice was markedly impaired.The EF and FS were significantly decreased from（92.1 ±3.45）% and（61.4 ±2.85）% to（49.8 ±14.20）% and（26.1 ±9.01）%（P 0.001）,while EED and ESD were increased significantly [（35.9 ± 3.12）μm and（13.9 ± 1.98）μm vs.（48.9 ± 6.05）μm and（36.5 ±7.37）μm,P 0.001,respectively].Pathological examination confirmed scar formation.Conclusions A mouse model of myocardial infarction has been successfully established by surgical ligation of the left anterior descending coronary artery and the heart functions can be evaluated by echocardiography.