【作者】 李立卓；

【导师】 姜志安；

【作者基本信息】 河北医科大学 ， 内科学， 2010， 硕士

【摘要】 目的:急性心肌梗死(acute myocardial infraction, AMI)后,出现心室重构,进而发展为心力衰竭(heart failure, HF),终因心力衰竭而导致死亡,目前HF尚无有效的治疗方法,故预防心室重构至关重要。近年来研究表明,心肌细胞凋亡也是心肌细胞的一种重要的死亡形式,在AMI后的心室重塑中起了很重要的作用。Rho激酶介导了一系列的细胞生物学行为,包括细胞凋亡。本研究通过观察大鼠急性心肌梗死(acute myocardial infarction, AMI)后心肌梗死面积、心肌细胞凋亡及Bcl-2和Bax表达的情况,以评价不同剂量Rho激酶抑制剂(法舒地尔, Fasudil)对大鼠AMI后心肌的保护作用。方法:健康雄性Sprague Dawley(SD)大鼠54只随机分为5组,假手术组(Sham):仅在左冠状动脉前降支(LAD)下穿线但不结扎;AMI组:结扎LAD;法舒地尔大剂量治疗组(High dose fasudil treated, HDFT):结扎LAD;法舒地尔中剂量治疗组(Intermediate dose fasudil treated, IDFT):结扎LAD;法舒地尔小剂量治疗组(Low dose fasudil treated, LDFT):结扎LAD。术前1h Sham组和AMI组分别给予生理盐水0.5ml腹腔注射,术前1h法舒地尔大剂量治疗组给予法舒地尔30mg/kg腹腔注射,法舒地尔中剂量治疗组给予法舒地尔10mg/kg腹腔注射,法舒地尔小剂量治疗组给予法舒地尔1mg/kg腹腔注射。术后24h,伊文蓝-红四氮唑双染色,确定缺血面积和梗死面积,TUNEL法检测缺血区凋亡细胞,免疫组织化学染色法检测缺血区Bcl-2和Bax的表达。结果:1心肌梗死面积的比较与AMI组相比,HDF组与IDF组大鼠的心肌梗死面积均显著下降,且差别有统计学意义(P<0.01);LDF组大鼠的心肌梗死面积与AMI组相当,差别无统计学意义(P >0.05);IDF组较LDF组大鼠的心肌梗死面积显著下降,且差别有统计学意义(P<0.01)。2 Bcl-2蛋白表达的比较与Sham组相比,AMI组、LDF组、IDF组及HDF组缺血区心肌细胞Bcl-2蛋白的表达均显著降低,且差别有统计学意义(P <0.01);与AMI组相比,HDF组和IDF组Bcl-2蛋白的表达均显著升高,且差别有统计学意义(P <0.01);与AMI组相比,LDF组Bcl-2蛋白的表达升高,但差别无统计学意义(P >0.05);HDF组和IDF组比较Bcl-2蛋白的表达显著升高,差别有统计学意义(P<0.01);IDF组和LDF组比较Bcl-2蛋白的表达显著升高,差别有统计学意义(P<0.01)。3 Bax蛋白表达的比较与Sham组相比,AMI组、LDF组、IDF组及HDF组缺血区心肌细胞Bax蛋白的表达均显著升高,且差别有统计学意义(P <0.01);与AMI组相比,LDF组、IDF组及HDF组Bax蛋白的表达均显著降低,且差别有统计学意义(P<0.01);HDF组和IDF组比较Bax蛋白的表达显著降低,差别有统计学意义(P <0.01);IDF组和LDF组比较Bax蛋白的表达显著降低,差别有统计学意义(P <0.01)。4心肌细胞凋亡的比较与Sham组相比,AMI组、LDF组、IDF组及HDF组缺血区心肌细胞凋亡指数均显著升高,且差别有统计学意义(P <0.01);与AMI组相比,LDF组、IDF组及HDF组心肌细胞凋亡指数均显著降低,且差别有统计学意义(P<0.01);HDF组和IDF组比较心肌细胞凋亡指数显著降低,差别有统计学意义(P <0.01);IDF组和LDF组比较心肌细胞凋亡指数显著降低,差别有统计学意义(P <0.01)。结论:本研究对AMI后大鼠应用不同剂量法舒地尔干预,结果显示法舒地尔具有以下作用:1提高AMI后缺血区Bcl-2的表达。2降低AMI后缺血区Bax的表达。3减少AMI后缺血区细胞凋亡水平。4减低AMI后的心肌梗死面积。以上作用与剂量相关,大剂量的作用较强。更多还原

【Abstract】 Objective: The ventricular remodeling after acute myocardial infarction (AMI), and then the heart failure (HF), eventually lead to death. Currently, there is no effective treatment to prevent it, so the prevention of ventricular remodeling is essential. Recent studies have shown that cardiomyocyte apoptosis is an imperative form of death and it play an important role in ventricular remodeling after acute myocardial infarction. Rho-kinase mediated a series of behavior of cell biology, including cell apoptosis.In this study,myocardial infarction area,cardiomyocyte apoptosis and the expression of Bcl-2 and Bax were obtained after acute myocardial infarction(AMI) in rats,and to study the protection effects of different doses fasudil,a Rho-kinase inhibitor ,on the myocardium of rats with AMI.Methods: Fifty-four healthy male SD rats were subjected to left anterior descending coronary artery(LAD) ligation and were divided randomly into five groups:Sham operation group(not ligation of LAD) ,AMI group, high dose fasudil treated(HDFT) group, intermediate dose fasudil treated(IDFT) group and Low dose fasudil treated (LDFT)group. 1h before surgery the rats received intraperitoneal injection normal saline 0.5ml ( sham group and AMI group) ,30mg/kg fasudil (HDFT group), 10mg/kg fasudil(IDFT group) and 1mg/kg fasudil(LDFT group). At 24 hours after coronary ligation,the rats were sacrificed.The myocardial infarction area and ischemia area were determined by evans-bule and TTC double staining.The cardiocyte apoptosis in the ischemia region was determined by TUNEL assay and the apoptotic index(AI) were calculated.The Bcl-2 and Bax protein expressions were measured by immunohistochemical staining.Results: 1 Compared with the AMI group, the myocardial infarction area reduced obviously in HDF group and IDF group(P <0.01);There was not statistically significant between LDF group and AMI group(P >0.05);Compared with the LDF group, the myocardial infarction area reduced obviously in IDF group(P<0.01).2 Compared with the Sham group, the expression of Bcl-2 reduced obviously in AMI group, LDF group, IDF group and HDF group(P <0.01);Compared with the AMI group, the expression of Bcl-2 increased obviously in HDF group and IDF group(P <0.01);There was not statistically significant between AMI group and LDF group(P >0.05);Compared with the IDF group, the expression of Bcl-2 increased obviously in HDF group(P<0.01). Compared with the LDF group, the expression of Bcl-2 increased obviously in LDF group(P<0.01).3 Compared with the Sham group, the expression of Bax increased obviously in AMI group, LDF group, IDF group and HDF group(P <0.01);Compared with the AMI group, the expression of Bax reduced obviously in LDF group, IDF group and HDF group(P <0.01);Compared with the IDF group, the expression of Bax reduced obviously in HDF group(P<0.01). Compared with the LDF group, the expression of Bax reduced obviously in IDF group(P<0.01).4 Compared with the Sham group, the cardiomyocyte apoptotic index increased obviously in AMI group, LDF group, IDF group and HDF group(P <0.01);Compared with the AMI group, the cardiomyocyte apoptotic index reduced obviously in LDF group, IDF group and HDF group(P <0.01);Compared with the IDF group, the cardiomyocyte apoptotic index reduced obviously in HDF group(P<0.01). Compared with the LDF group, the cardiomyocyte apoptotic index reduced obviously in IDF group(P<0.01).Conclusion: Different Doses Fasudil intervention after AMI in rats can be illustnated as follows, (1) increase the expression of Bcl-2.(2) reduce the expression of Bax.(3) reduce the Cardiocyte apoptosis.(4) reduce the myocardial infarction area. These effects has dose-dependently, and the higer dose the better results.更多还原