反复心肌缺血致心肌梗死模型的制备

目的：本研究通过大鼠反复心肌缺血并叠加冠状动脉结扎手术建立反复心肌缺血至心肌梗死模型。方法：通过大鼠尾静脉反复缓慢推注垂体后叶素诱发大鼠心肌缺血，叠加冠状动脉左前降支结扎手术建立大鼠反复心肌缺血致心肌梗死模型。以心电图、生化指标肌酸激酶同工酶（CK-MB）、谷草转氨酶（AST）、丙氨酸氨基转移酶（ALT）及心肌梗死范围]为指标，确定最佳造模条件。以通心络胶囊为阳性药，以生化指标肌酸激酶同工酶（CK-MB）、乳酸脱氢酶（LDH）、丙氨酸氨基转移酶（ALT）及心肌梗死范围为指标验证该模型用于评价中药治疗心肌缺血的可行性。结果：垂体后叶素15U?kg^-1给药后与7.5 U?kg^-1比较大鼠心肌缺血出现所需时间较短，心肌缺血持续时间均可稳定在20 min 以上，与30 U?kg-1 比较动物死亡率低；垂体后叶素给药3天，心肌缺血持续时间均可稳定在30min以上，与假手术组比较心肌酶显著升高，动物死亡率低。通心络胶囊组与模型组比较心肌梗死体积显著减小（P<0.05）、血清酶LDH、CK-MB、ALT活性值明显降低（P<0.05）。结论：大鼠尾静脉推注垂体后叶素15U?kg^-1，反复给药3天为最佳造模条件。大鼠反复心肌缺血致心肌梗死模型适于评价中药的抗心肌缺血作用。

Research on Method of Repeated Myocardial Ischemia to Myocardial Infarction Model in Rats

This study aimed to confirm model of the repeated myocardial ischemia to myocardial infarction model in rats.The model was induced by injecting vasopressin repeatedly via the tail vein slowly for several days.And then,the left anterior descending coronary artery was ligated.The electrocardiogram(ECG),biochemical indicators(CK-MB,AST,ALT)and the myocardial infarction volume were taken as indexes for the determination of optimized conditions for the model.Tongxinluo(TXL)capsule was chosen as positive drug.Biochemical indicators,including CK-MB,LDH,ALT,and the myocardial infarction volume were used to evaluate the feasibility of Chinese medicine in anti-ischemic treatment of the new model.The results showed that in the appear time of myocardial ischemia the vasopressin 15U?kg^-1 group was significantly lower than the vasopressin 7.5U?kg^-1 group.The duration of myocardial ischemia was more than 20min.The mortality rate of rats was lower compared to the vasopressin 30U?kg^-1 group.After 3-day vasopressin,the duration of myocardial ischemia was more than 30min.Compared with the sham operation group CK-MB was significantly increased with low mortality rate of rats.The myocardial infarction volume of TXL capsule group was significantly decreased compared with the model group(P<0.05).The activities of serum enzymes(LDH,CK-MB and ALT)were significantly lower than model group(P<0.05).It was concluded that the optimal model establishment condition was to inject 15U?kg^-1 of vasopressin via the tail vein repeatedly for three days.The model of repeated myocardial ischemia to myocardial infarction model was adapted to evaluate the anti-ischemic effect of Chinese medicine.