重组人脑利钠肽对急性心肌梗死大鼠心功能和心肌细胞凋亡的影响

摘要

目的 观察重组人脑利钠肽对急性心肌梗死(AMI)大鼠心功能和心肌细胞凋亡的影响.方法 通过结扎100只SD大鼠左冠状动脉前降支建立AMI模型,随机分为观察组和对照组各50只.观察组予重组人脑利钠肽15 ug/kg、连续4周,对照组予等体积生理盐水.两组分别于治疗48 h、1周、2周、3周和4周时采用超声检测左室射血分数(LVEF),处死大鼠并取血测定血浆BNP浓度,原位末端标记法(TUNEL法)测定心肌细胞凋亡指数(MAI),免疫组化法检测Fas、FasL蛋白阳性染色指数.结果 与对照组比较,观察组LVEF在第48 h即有明显升高(P＜0.05);观察组MAI治疗后3、4周与48 h比较下降明显(P均＜0.05),观察组治疗4周时与对照组比较亦有明显下降(P＜0.05).观察组于2、3、4周时Fas/Fasl蛋白阳性率明显低于48 h时(P均＜0.05),且与对照组比较下降明显(P均＜0.05).结论 连续予重组人脑利钠肽能够通过减少大鼠AMI后心肌细胞凋亡,达到改善心功能的目的.%Objective To assess the effects of recombinant human brain natriuretic peptide ( rhBNP) on the cardiac function and myocardial apoptosis of rats with acute myocardial infarction ( AMI). Methods AMI models were made in 100 SD rats by ligaturing the left coronary artery main stem of rats hearts. Then, the rats were divided into observed group and control group with 50 in each. Rats in observed group received rhBNP15ug/kg for 4 weeks. After treatment of 48 h, 1 week, 2 weeks, 3 weeks and 4 weeks, left ventricular ejection fraction( LVEF) was detected by ultrasonography. Then the rats were executed, and the serum BNP level was examined, myocardial cell apoptosis index ( MAI) was determinated by TUNEL and immunohistochemical detection of Fas/FasL protein positive staining index were analyzed as well. Results LVEF in observed group was significantly higher 48 h after the treatment, as compared with that in control group ( P < 0.05). MAI in the observed group after the treatment of 3 and 4 weeks decreased significantly, compared with that of 48 h (P<0.05) and which in control group 4 weeks after the treatment(P <0.05). The positive rate of Fas/FasL protein in myocardium decreased significantly 2 ,3 and 4 weeks after the treatment, compared with that of 48 h (P < 0. 05) and which in control group (P < 0. 05 ). Conclusion rhBNP injected continuously for 4 weeks may efficiently improve the heart function of rats after myocardial infarction by inhibiting the cardiocyte apoptosis.