5-杂氮-2’-脱氧胞苷改善高同型半胱氨酸血症大鼠内皮功能的机制  

Effects and related mechanism of 5-aza-2＇-deoxycytidine on endothelial function in rats withhyperhomocysteinemia

作　　者：高胜利[1] 李莉[3] 翟晓娟[3] 郭任维[3] 高淑红 

机构地区：[1]山西医科大学汾阳学院生理学教研室,032200 [2]统计学教研室 [3]山西医科大学附属汾阳医院心血管内科

出　　处：《中华心血管病杂志》2016年第8期700-706,共7页Chinese Journal of Cardiology

摘　　要：目的探讨5－杂氮－2＇－脱氧胞苷（Aza）改善高同型半胱氨酸血症大鼠内皮功能的机制。方法SD成年雄性大鼠按照随机数字表法分为3组：对照组采用基础饲料饲养（n＝7）；高同型半胱氨酸血症（HHcy）组在基础饲料上添加3%L－蛋氨酸（n＝7）；Aza组（n＝7）在基础饲料上添加3%L－蛋氨酸，并腹腔注射Aza（0.5 mg/kg），每周连续3 d，每天1次，共注射8周。8周后，采用ELISA检测大鼠血浆同型半胱氨酸含量，检测大鼠肠系膜动脉内皮依赖性舒张功能功能，采用硝酸还原酶法检测大鼠肠系膜动脉一氧化氮含量，采用ELISA检测大鼠肠系膜内皮一氧化氮合酶（eNOS）活性和非对称二甲基精氨酸（ADMA）含量，采用实时荧光定量PCR检测大鼠肠系膜动脉二甲基精氨酸二甲胺水解酶2（DDAH2）和DNA甲基转移酶1（DNMT1）的mRNA表达水平，采用Western blot检测大鼠肠系膜动脉DDAH2和DNMT1的蛋白质表达水平，采用巢式甲基化PCR检测大鼠肠系膜动脉DDAH2启动子甲基化水平。结果（1）HHcy组和Aza组的同型半胱氨酸含量均高于对照组[（29.00±0.94）μmol/L、（26.43±0.47）μmol/L比（10.34±0.63）μmol/L，P均〈0.01]，而且HHcy组的同型半胱氨酸含量高于Aza组（P〈0.05）。（2）给予不同浓度乙酰胆碱后，HHcy组血管环的舒张百分比均低于对照组（P均〈0.05），Aza组血管环的舒张百分比均高于HHcy组（P均〈0.05）；给予不同浓度硝普钠后，3组血管环的舒张百分比差异均无统计学意义（P均〉0.05）。（3）HHcy组肠系膜动脉一氧化氮含量低于对照组[（0.42±0.00）μmol/g比（0.52±0.01）μmol/g, P〈0.01]，Aza组肠系膜动脉一氧化氮含量[（0.49±0.01）μmol/g]高于HHcy组（P〈0.01）。HHcy组肠系膜动脉eNOS活性低于对照组[（0.57±0.00）U/mg比（0.74±0.01）U/mg，P〈0.01]，Aza组肠系膜动脉eNOS活性[（0.65±0.01）U/mg]高于HHcy组（P〈0.01�Objective To investigate the effects and related mechanism of 5-aza-2＇-deoxycytidine （Aza） on endothelial function in Hyperhomocysteinemia rats. Methods Adult male SD rats were divided into 3 groups （n = 7 each） ： control group, hyperhomocysteinemia （Hhcy） group and Aza group according to the random number table. Control group rats were fed with normal diet. Hhcy group rats were fed with diet adding 3% L-methionine. Aza group rats were fed with diet adding 3% L-methionine and Aza （0. 5 mg/kg） injection for consecutive three days per week for 8 weeks. After 8 weeks, content of rat plasma homocysteine （Hey） was detected by enzyme linked immunosorbent assay （ELISA）. The rat mesenterie artery endothelium-dependent diastolic function was detected. The nitric oxide synthase （eNOS） activity and asymmetric dimethyl fine ammonia acid （ADMA） content were detected by ELISA,and the content of nitric oxide was detected by nitrate reductase method in the mesenteric arteries. The mRNA expression of DNA methyl transferase 1 （ DNMT1 ） and dimethyl arginine acid dimethylamine hydrolase 2 （ DDAH2 ） in the mesenteric arteries were detected by real-time fluorescence quantitative PCR, and the protein expressions of DNMT1 and DDAH2 in the mesenteric arteries were detected by Western blot. The DDAH2 promoter methylation level in the mesenterie arteries was detected by nested methylation specific PCR. Results （ 1 ） The content of plasma Hcy was significantly higher in the Hhcy group and Aza group compared to the control group （（29.00 ±0.94） μmol/L and （26.43 ±0.47） μmol/L vs. （10.34 ±0.63） μmol/L, both P 〈 O. O1 ） , which was significantly reduced in the Aza group compared with the Hhcy group （P 〈0. 05）. （2） Acetylcholine-mediated relaxation at various concentrations was significantly lower in the Hhcy group and the Aza group compared with the control group （ both P 〈 0. 05 ）, which was significantly increased in Aza group compared with Hhcy group �

关 键 词：高半胱氨酸 血管舒张 内皮 

分 类 号：R54[医药卫生—心血管疾病]