【摘要】 目的　探讨大鼠心肌缺血后不同再灌注时相心肌细胞凋亡、Ｆａｓ 基因表达变化及缺血预处理的影响。方法　１０８ 只大鼠随机分成假手术组（ 假手术２４ 小时） ，缺血３０ 分钟再灌注６ 、１２、２４、４８小时组及缺血预处理（ＩＰＣ） 组（ 结扎冠脉５ 分钟、再灌注５ 分钟，重复３ 次后再行结扎冠脉３０ 分钟，再灌注６ 小时） 。以缺口末端标记法（ＴＵＮＥＬ） 标记凋亡细胞，以ＳＰ免疫组化及逆转录聚合酶链反应（ＲＴＰＣＲ） 法分别检测Ｆａｓ 基因蛋白与ｍＲＮＡ的表达变化。结果　心肌细胞凋亡与Ｆａｓ 基因的表达水平随心肌再灌注不同时相而变化，其中细胞凋亡指数（ＡＩ） 与Ｆａｓ 基因蛋白表达指数（ＰＥＩ） 于再灌注４８小时最高［ＡＩ：（３８．１５±１３．２６）％ ；Ｆａｓ ＰＥＩ：（２４ ．７７ ±１２．９２） ％］ ；Ｆａｓ 基因ｍＲＮＡ表达于再灌注２４ 小时达高峰（Ｆａｓ／βａｃｔｉｎ：０．７６±０．２１）；Ｆａｓ 基因ＰＥＩ与心肌细胞ＡＩ间存在良好的相关性（ｒ＝０．８７ ， Ｐ＜０－０１）；ＩＰＣ可抑制心肌细胞凋亡，并下调Ｆａｓ 基因的蛋白表达（ Ｐ值均＜ ０．０５）。结论　心肌细胞凋亡与Ｆａｓ基因的表达水平因再灌注不同时相而变化，细胞凋亡及Ｆ?更多还原

【Abstract】 Objective To study the changes of apoptosis and Fas gene expression in cardiomyocytes of rats with different duration of reperfusion after myocardial ischemia and the effects of ischemic preconditioning (IPC). Methods 108 rats were divided randomly into 6 groups, i.e. sham operated (observing for 24h in operated control ), 30min of ischemia followed by 6h of reperfusion(I 30 min R 6h ), I 30min R 12h , I 30min R 24h , I 30min R 48h and IPC. The myocardial cell apoptosis was determined with terminal deoxynucleotidyl transferase mediated dUTP fluorescein nick end labeling (TUNEL) method; The protein and mRNA expression of Fas gene were studied with S P immunohisto chemical staining and RT PCR analysis respectively. Results Cardiomyocyte apoptosis and the level of Fas gene expression varied with the duration of reperfusion. The apoptotic index(AI) and protein expression index (PEI) of Fas gene in myocytes were highest in rats with I 30min R 48h [AI: (38.15±13.26)%; Fas PEI: (24 77±12.92)%], but mRNA induction peaked at I 30min R 24h (Fas/β actin:0.76±0.21); PEI of Fas gene correlated significantly with AI of myocytes ( r =0.87, P <0.01);IPC decreased myocyte apoptosis and down regulated the protein expression of Fas gene(all P <0.05). Conclusion The number of apoptotic myocytes and the expression level of Fas gene varied with different duration of myocardial reperfusion. The change of apoptosis and Fas gene expression may be involved in the process of myocardial ischemia reperfusion injury. IPC prevent myocardial injury partly by inhibiting myocyte apoptosis and down regulating protein expression of Fas gene.更多还原