早期氯沙坦干预对成年自发性高血压大鼠心肌DNA甲基化转移酶的影响  

Effect of early treatment with losartan on myocardial DNA methyltransferase in the later life of spontaneously hypertensive rats

作　　者：王庭俊 练桂丽 林旭 陈婉茹 钟鸿斌 谢良地 

机构地区：[1]福建医科大学附属第一医院,福建省高血压研究所,福建福州350005

出　　处：《中华高血压杂志》2018年第1期29-35,共7页Chinese Journal of Hypertension

基　　金：福建省自然科学基金项目(2017J01193); 福建省中青年骨干人才培养项目(2017-ZQN-44)

摘　　要：目的探讨早期氯沙坦干预对成年自发性高血压大鼠(SHR)心肌DNA甲基化转移酶(DNMT)家族中DNMT1、DNMT3a、DNMT3b的影响及其与血管紧张素Ⅱ1型受体相关蛋白(ATRAP)基因启动子区甲基化水平的关系。方法按氯沙坦给药时期将Wistar-Kyoto(WKY)母鼠、SHR母鼠及相应子鼠分为WKY未干预组、SHR未干预组、SHR出生前干预组、SHR出生后干预组、SHR序贯干预组。每组选取8只雄性子鼠用于实验。在子鼠16周龄时,应用尾测法测量血压,称重法测量并计算左心室质量/体质量,重亚硫酸盐修饰聚合酶链反应(PCR)结合焦磷酸测序检测ATRAP基因启动子区的甲基化水平,Western-blot检测大鼠心肌中3种DNMT的表达,染色质免疫共沉淀检测DNMT与ATRAP基因启动子区的相互作用。结果与SHR未干预组相比,SHR出生前干预组、出生后干预组及序贯干预组的血压和左心室质量/体质量降低(均P<0.05),心肌中ATRAP基因启动子区的甲基化水平减少(P<0.05),DNMT1、DNMT3a、DNMT3b的表达差异无统计学意义(P>0.05),但DNMT1、DNMT3a与ATRAP基因启动子区的相互作用减弱(DNMT1:0.9±0.1,0.9±0.1,1.0±0.1比2.9±0.3;DNMT3a:1.0±0.2,1.1±0.2,1.1±0.2比3.0±0.3,均P<0.05)。结论早期氯沙坦干预可减弱DNMT1、DNMT3a与ATRAP基因的相互作用,这可能与SHR心肌中ATRAP基因启动子区的甲基化水平降低有关。Objective To investigate the effect of early treatment with losartan on myocardial DNA methyltransferase（DNMT）family members：DNMT1,DNMT3 aand DNMT3 bin the later life of spontaneously hypertensive rats（SHR）,and to explore the relationship of the DNMT changes and methylation level of angiotensinⅡtype 1 receptor-associated protein（ATRAP）gene promoter. Methods Maternal Wistar-Kyoto（WKY）rats,SHR and their offspring were divided into untreated WKY group,untreated SHR group,prenatal losartan-treated SHR group,postnatal losartan-treated group and sequential losartan-treated group. At the age of sixteen weeks,male offspring was used in the experiment with eight rats in each group. Blood pressure was measured by tail-cuff method,and left ventricular mass and body mass were measured and their ratio was calculated. Methylation level of ATRAP gene promoter in myocardium was determined by bisulfite sequencing polymerase chain reaction.DNMT1,DNMT3 aand DNMT3 bexpression were determined by Western-blot. Interaction between DNMT and ATRAP gene promoter was analyzed by chromatin immunoprecipitation assay. Results Blood pressure and left ventricular mass/body mass were all lower in prenatal,postnatal and sequential losartan-treated SHR than in untreated SHR.Methylation level of ATRAP gene promoter was lower in the three early treatment groups than in untreated SHR group.There was no significant difference in DNMT1,DNMT3 aand DNMT3 bexpression among the three early treatment groups and untreated SHR group,however,the interaction between DNMT1,DNMT3 aand ATRAP gene promoter was lower in the three early treatment groups than in untreated SHR group（DNMT1：0.9±0.1,0.9±0.1,1.0±0.1 vs 2.9±0.3;DNMT3 a：1.0±0.2,1.1±0.2,1.1±0.2 vs 3.0±0.3,all P〈0.05）. Conclusion Early treatment with losartan reduces the interaction between DNMT1,DNMT3 aand ATRAP gene promoter in myocardium of SHR,which may be related to the decreased methylation level of ATRAP gene promoter.

关 键 词：高血压 左心室肥厚 血管紧张素Ⅱ1型受体相关蛋白 DNA甲基化 DNA甲基化转移酶 

分 类 号：R544.1[医药卫生—心血管疾病]