作　　者： ; ; ; ; ; (覃军）;

机构地区： 顺德职业技术学院医学系

出　　处： 《中国动脉硬化杂志》 2005年第3期271-274,共4页

摘　　要： 目的通过建立大鼠心肌梗死模型,观察急性心肌梗死对大鼠心脏内皮型一氧化氮合酶mRNA和诱导型一氧化氮合酶蛋白表达的影响。方法48只健康成年SD大鼠(体重200～250g)随机分为假手术组和缺血组,取1、2、8和24h四个不同时间点观察。采用开胸结扎冠状动脉左前降支建立心肌缺血模型,逆转录聚合酶链反应检测大鼠心肌梗死后1、2及24h三个时段缺血心肌内皮型一氧化氮合酶mRNA的表达;免疫组织化学染色检测冠状动脉结扎后8h缺血心肌诱导型一氧化氮合酶蛋白的表达。结果冠状动脉结扎后2h,缺血组大鼠缺血心肌组织内皮型一氧化氮合酶mRNA表达下降(P<0.05),并持续至结扎后24h;结扎后24h组内皮型一氧化氮mRNA的表达与结扎后2h组相比无显著性差异(P>0.05)。冠状动脉结扎后8h,梗死区存活心肌组织细胞诱导型一氧化氮合酶蛋白大量表达,而假手术组未见诱导型一氧化氮合酶蛋白表达。结论正常大鼠心肌组织有内皮型一氧化氮合酶基因表达,无诱导型一氧化氮合酶蛋白表达。在心肌梗死早期缺血心肌内皮型一氧化氮合酶mRNA表达减少。心肌急性缺血刺激早期诱导大鼠缺血心肌组织诱导型一氧化氮合酶蛋白大量表达。 Aim To observe the mRNA expression of endothelial nitric oxide sythase （eNOS） at different time intervals after acute myocardial infarction in rat hearts and examine the effect of acute myocardial ischemic stimulation on the protein producfion of inducible nitric oxide sythase （iNOS） in rat hearts. Methods Forty-eight healthy Sprague-Dawley rats （200250 g） were randomly divided into two groups： control group and ischemia group. Myocardial ischemia was induced by the left anterior descending coronary artery （LAD） ligation. Animals with LAD occlusion （ ischemia group） were sacrificed at 1 h, 2 h, 8 h, and 24 h after operation. The eNOS gene expression in ischemic myocardium was assessed using reverse transcriptase-polymerase chain reaction （RT-PCR） standardized with β-actin; the iNOS protein in spare cardiomyocytes in the infarcted region after operational 8h was detected using immunohistochemedical analysis. Results Ligating of LAD for 2 h decreased significantly the eNOS mRNA levels in iscliemic myocardial tissue compared with that in controls （P〈 0.05） . The decent of eNOS mRNA level sustained for postperational 24 h. There is no significant difference in expression level between ligating for 2 h group and ligating for 24 h group, iNOS protein was abundant in the 8 h infarcted heart in spared cardiomyocytes in the infarcted region. Staining of sham-operated rat hearts indicated the absence of iNOS protein. Significant difference in expression levels were observed between ischemia experiment groups and sham-operated control groups （P〈0.01）. Conclusion The eNOS gene expressed in normal rat hearts, whereas there was no iNOS protein expression in normal rat hearts. The expression of eNOS mRNA in ischemic myocardium after myocardial infarction in rats decreased in the early time. Acute myocardial infarction induced iNOS protein levels expressing abuntantly in the ischemic myocardium tissue in rats.

关 键 词： 分子生物学 心肌梗死时一氧化氮合酶的表达 逆转录聚合酶链反应 急性心肌梗死 内皮型一氧化氮合酶 诱导型一氧化氮合酶 大鼠

领　　域： [生物学]