RNA干扰联合基因沉默ACE和AT1R对自发性高血压大鼠血压及心肌重构的影响  

Effects of RNA interference targeting angiotensin 1 receptor and angiotensin-converting enzyme on blood pressure and myocardial remodeling in spontaneous hypertensive rats

作　　者：周华[1] 边云飞[1] 李茂莲[1] 高奋[1] 肖传实[1] 

机构地区：[1]山西医科大学第二医院心内科,太原030001

出　　处：《中华心血管病杂志》2010年第1期60-66,共7页Chinese Journal of Cardiology

基　　金：山西省归国留学人员基金资助（2007005）;山西省研究生优秀创新项目（20081050）;山西省卫生厅科技攻关项目（200933）

摘　　要：目的用RNA干扰技术下调血管紧张素转换酶（ACE）和血管紧张素Ⅱ1型受体（AT1R）表达，观察其对自发性高血压大鼠（SHR）血压及心肌重构的影响。方法SHR随机分为5组：即空白对照组（注射生理盐水）；病毒对照组（注射对照腺病毒）；Ad5-ACE-shRNA治疗组；Ad5—AT1R-shRNA治疗组；Ad5—ACE—AT1R—shRNA治疗组[分别注射表达ACE基因，AT1R基因，ACE和AT1R基因特异短发夹RNA（shRNA）的重组腺病毒载体]；同时设WKY正常血压对照组（注射生理盐水）。以上各组大鼠均于实验的第1，17天各注射1次，干预前后检测血压、心率的变化。于首次注射后第3天，用实时荧光定量PCR检测心肌、主动脉组织ACE，AT1R mRNA的表达。实验结束时，检测左心重／体重及心肌胶原蛋白的含量，并做电镜切片观察心肌超微结构的变化。结果Ad5-ACE-shRNA治疗组，Ad5—AT1R-shRNA治疗组，Ad5—ACE-AT1R-shRNA治疗组于每次注射后，尾动脉压分别下降24mmHg（1mmHg=0．133kPa）、22mmHg、26mmHg左右，单次注射后降压作用至少可持续15d，累计降压幅度分别达39mmHg、37mmHg、43mmHg；而SHR空白对照和病毒对照组血压则持续升高约26mmHg，且两组比较差异无统计学意义；WKY组尾动脉压无明显变化，治疗组（Ad5-ACE—shRNA，Ad5-ACE-AT1R—shRNA）心肌、主动脉组织中ACE mRNA和治疗组（Ad5-AT1R—shRNA，Ad5—ACE-AT1R—shRNA组）心肌、主动脉组织中AT1R mRNA表达明显低于空白对照和病毒对照组（P〈0．05），而与WKY组比较差异无统计学意义。Ad5-ACE—shRNA治疗组，Ad5-T1R-shRNA治疗组，Ad5-ACE-AT1R—shRNA治疗组左心重／体重与心肌胶原蛋白含量[（2．22±0．18）μg／mg、（2．23±0．19）μg／mg、（2．17±0．16）μg／mg与（1．291±0．019）μg／mg、（1．298±0．019）μg／mg、（1．276±0．019）μg／mg]明显低于空白对照组[（3．23±0．13）μg／mg与（1．683±0．013�Objective To investigate the effects of RNA interference （RNAi） targeting angiotensin Ⅱ Type 1 receptor （AT1R） and angiotensin-eonverting enzyme （ACE） on blood pressure and myocardial remodeling in spontaneous hypertensive rats （SHRs）. Methods Saline （ control）, adenovirus （ADS） and recombinant adenoviral vectors （ Ad5-ACE-shRNA, Ad5-AT1R-shRNA and Ad5-ACE-AT1R-shRNA expressing ACE, AT1R, ACE and AT1R gene-specific shRNA, respectively） were randomly administered by caudal intravenation to SHRs （n = 12 each group） at day 1 and 17. Normotensive Wistar-Kyoto rats （WKY） served as normal controls. Systolic blood pressure （SBP） of the caudal artery was measured daily. Expression of ACE and AT1R at mRNA levels in ventricle and aorta were evaluated by fluorescence quantitative PCR. Angiotension Ⅱ serum concentration was measured by ELISA at day 3 （ n = 6 each group）. The ratio of left ventricular to body weight （LVW/BW） and myocardial collagen content were measured, myocardial ultrastructure observed under transmission electron microscope at the study end. ResUlts The caudal artery pressure of saline and Ad5 group was equally increased by about 26 mm Hg （ 1 mm Hg=0. 133 kPa） compared to baseline （both P 〈0. 05）. Ad5-ACE-shRNA,Ad5-AT1R-shRNA and Ad5-ACE-ATI R-shRNA injection significantly reduced SBP （ -24 mm Hg, -22 mm Hg and -26 mm Hg respectively, all P 〈0.05 vs. baseline） and the antihypertensive effect could last at least 15 days post each injection. SBP was not affected by saline and Ad5 injections. ACE and AT1 mRNA expressions at ventricle and aorta were significantly decreased in Ad5-ACE-shRNA, Ad5-ACE-AT1R-shRNA and Ad5-AT1R- shRNA, Ad5-ACE-AT1R-shRNA treated SHRs compared to those in saline and Ad5 groups （ all P 〈 0.05 ） and was comparable to that in WKY group （P 〉0.05）. The LVW/BW ratio [ （2.22 s0.18） ixg/mg, （2.23 ±0.19） μg/mg, （2. 17 ± 0. 16） μg/mg] and myocardial collagen content [ （ 1. 291 ± 0. 019 ） μg/mg

关 键 词：高血压 RNA干扰 心室重构 大鼠 

分 类 号：R544.1[医药卫生—心血管疾病] R512.62[医药卫生—内科学]