阻断整合素α4对大鼠心肌梗死后心功能的影响

Effect of blockingα4 integrin on cardiac function after myocardial infarction in rats

目的探讨阻断整合素α4对大鼠心肌梗死后心功能的影响。方法 28只雌性SD大鼠,通过结扎冠状动脉左前降支,建立心肌梗死模型后,随机分为实验组和对照组,每组14只。实验组腹腔内注射整合素α4抗体,对照组注射同种型对照抗体IgG。造模2和4周后,心脏超声测量大鼠心功能,Western blot检测心肌梗死区血小板生长因子(PDGF)、血管生长因子(VEGF)和血管生长因子受体2(FLK-1)蛋白表达,并测量心肌梗死面积。结果与对照组比较,实验组大鼠心功能明显升高;心肌梗死区PDGF、VEGF和FLK-1蛋白表达明显升高;心肌梗死面积明显降低(P<0.05)。结论阻断整合素α4可以降低大鼠心肌梗死面积,提高心功能。

Objective To explore the effect of blocking α4 integrin on cardiac function of female rat model of myocardial infarction. Methods Myocardial infarction model was created in 28 female rats by left anterior descending coronary artery ligation. All rats were randomly divided into treatment group and control group, treatment group received intraperitoneal injection of antibodies to α4 integrin （n = 14）,control group received injection of isotype control IgG antibody （n = 14）. Expression of platelet derived growth factor（PDGF）, vascular endothelial growth factor（VEGF） and VEGF receptor （FLK-1） in infarct area was examined by Western blot and cardiac function was examined by echocardiography after 2 and 4 weeks. Infarct size and myocardial contraction velocity were examined. Results Compared with control group, myocardial contraction velocity and cardiac function were significantly improved, expression of PDGF,VEGF and FLK-1 proteins was significantly increased, and infarct size significantly decreased in treatment group （P 〈0.05）. Conclusion Blocking α4 integrin can improve cardiac function and decrease infarct size.