论文部分内容阅读
目的比较对照组和干预治疗组大鼠心肌组织中基因表达的差异,探讨卡托普利保护心肌组织的作用。方法①实验于2002-08/2003-12在福建省立医院内分泌科完成。选用雄性SD大鼠12只。在空腹12h后按60m g/kg腹腔注入链脲佐菌素,每天注射1次,连续注射10周。5周后血糖浓度持续>16.6m m ol/L,表明已建立糖尿病模型。②10周后取大鼠部分心肌组织做电镜检查,发现线粒体变性,肌纤维收缩带形成,表明已建立糖尿病性心肌病动物模型。③将12只糖尿病性心肌病大鼠随机分为2组对照组和干预组,每组6只。干预组给予按1.5m g/(kg·d)给予卡托普利口服治疗15周;对照组正常饲养。两组均干预15周,然后将大鼠处死,取心肌组织作基因芯片检查。④经反转录分别用Cy3-dUTP和Cy5-dUTP标记对照组和干预组m RNA,获得两组动物来源的cDNA探针。cDNA探针与基因表达谱芯片杂交,结果由扫描仪扫描并用Im aGene3.0软件进行分析统计。以比率(Cy5/Cy3)>2为表达上调基因,以Cy5/Cy3<1为表达下调基因。结果大鼠12只均进入结果分析。①线粒体电子质子偶联和氧化磷酸化相关基因(反映心肌的能量供应)——质子泵基因、细胞色素P450,细胞色素C氧化酶亚单位Va、辅酶Q1b亚单位、泛素特异蛋白酶2Cy5与Cy3比率分别为2.684,2.387,3.124,3.213,3.234;肌动蛋白(在心肌收缩过程中起重要作用)基因Cy5与Cy3比率为2.277,线粒体电子质子偶联和氧化磷酸化相关基因、肌动蛋白基因在干预组中表达明显上调。②二甲基精氨酸水解酶(可产生一氧化氮,导致线粒体内氧自由基、过氧亚硝酸阴离子生成增加,导致呼吸链损伤)基因Cy5与Cy3比率为0.271,整合素b1(与心肌间质纤维化有关)基因Cy5与Cy3比率为0.286。二甲基精氨酸水解酶基因、整合素b1基因在干预组中表达明显下调。结论①卡托普利通过增强线粒体电子质子偶联和氧化磷酸化相关基因的表达,促进ATP的产生,保证了病变心肌的能量供应。②卡托普利可通过上调肌动蛋白基因表达,增强病变心肌的收缩力。③卡托普利可下调二甲基精氨酸水解酶基因表达,减少一氧化氮的产生,防止呼吸链的损伤。④卡托普利通过抑制整合素b1的表达,抑制心肌间质纤维化。
Objective To compare the difference of gene expression in myocardium between control group and intervention group, and to explore the role of captopril in protecting myocardium. Methods ① The experiment was performed in Department of Endocrinology of Fujian Provincial Hospital from August 2002 to December 2003. Twelve male SD rats were used. After 12 h of fasting, streptozotocin was injected intraperitoneally at a dose of 60 m g / kg once a day for 10 weeks. Blood glucose levels persisted> 16.6 m mol / L after 5 weeks, indicating that a diabetic model has been established. ② After 10 weeks, some myocardial tissue of rats were examined by electron microscopy. Mitochondrial degeneration and formation of muscle fiber contractile bands were found, which indicated that animal models of diabetic cardiomyopathy were established. ③ 12 diabetic rats with cardiomyopathy were randomly divided into 2 control and intervention groups, 6 in each group. The intervention group was given captopril orally for 15 weeks at 1.5 m g / (kg · d); the control group was reared normally. Both groups were intervened for 15 weeks, then the rats were killed and the myocardial tissue was taken for gene chip examination. (4) Two sets of animal-derived cDNA probes were obtained by labeling the control group and the intervention group with Cy3-dUTP and Cy5-dUTP respectively by reverse transcription. The cDNA probes were hybridized with the gene expression microarray, and the results were scanned by a scanner and analyzed with Im aGene 3.0 software. Up-regulated genes were expressed at a ratio (Cy5 / Cy3)> 2, and genes were down-regulated at Cy5 / Cy3 <1. Results All 12 rats were involved in the result analysis. ① mitochondrial electron proton coupling and oxidative phosphorylation related genes (reflecting the myocardial energy supply) - proton pump gene, cytochrome P450, cytochrome C oxidase subunit Va, coenzyme Q1b subunit, ubiquitin-specific protease 2Cy5 and Cy3 (2.684,2.387,3.124,3.213,3.234 respectively). The ratio of Cy5 to Cy3 in actin (which plays an important role in myocardial contraction) was 2.277, mitochondrial electron proton coupling and oxidative phosphorylation related genes, actin gene The expression in the intervention group was significantly increased. ② dimethylarginine hydrolase (can produce nitric oxide, resulting in mitochondrial oxygen free radicals, peroxynitrite anion generation increases, leading to respiratory chain injury) gene Cy5 and Cy3 ratio was 0.271, integrin b1 (and myocardial Interstitial fibrosis) gene Cy5 and Cy3 ratio of 0.286. Dimethylarginine hydrolase gene, integrin b1 gene was significantly downregulated in the intervention group. Conclusion ① Captopril promotes the production of ATP by enhancing the expression of mitochondrial electron proton coupling and oxidative phosphorylation-related genes, and ensures the supply of energy to diseased myocardium. Captopril can enhance myocardial contractility by up-regulating actin gene expression. Captopril down-regulated dimethylarginine hydrolase gene expression, reduced the production of nitric oxide and prevented the damage of the respiratory chain. ④ Captopril inhibits myocardial interstitial fibrosis by inhibiting the expression of integrin b1.