RNA干扰GPR14对自发性高血压大鼠血压和心血管重构的影响

Effects of RNA interference targeting GPR14 on blood pressure and cardiovascular remodeling in spontaneous hypertensive rats

目的观察RNA干扰技术下调尾加压素Ⅱ(UⅡ)特异性受体G蛋白偶联受体14(GPR14)对自发性高血压大鼠(SHR)血压和心血管重构的影响。方法 SHR或Wistar-Kyoto(WKY)大鼠均随机分为两组:裸病毒(Ad)对照组和Ad-GPR14-shRNA治疗组,分别尾静脉注射对照Ad和表达GPR14基因特异短发夹RNA(shRNA)的重组腺病毒载体Ad-GPR14-shRNA。注射前1周和注射后0、1、2、3、4周检测心脏、胸主动脉GPR14表达情况和尾动脉压变化情况。检测注射后2周心脏、胸主动脉和肠系膜上动脉组织病理学。结果 Ad-GPR14-shRNA注射后1周即显著降低WKY大鼠和SHR心脏、胸主动脉GPR14表达和尾动脉压,该效果可持续至第4周,2周时最明显,并且SHR大鼠降低更显著;Ad-GPR14-shRNA治疗2周时SHR组左心重/体质量显著下降、心肌细胞横断面积显著减少、心肌纤维化显著减弱、主动脉和肠系膜上动脉中膜厚度/官腔内径比值显著下降。结论 RNA干扰能有效降低心肌和血管GPR14表达,降低SHR血压并改善心血管重构,靶向GPR14的RNA干扰有望成为高血压病基因治疗的有效方法。

Objective To investigate the effects of the urotensin II （ U II ） specific receptor - GPR14 gene silence on blood pressure and cardiovascular remodeling in spontaneous hypertensive rats （SHR）. Methods Control adenovirus （Ad） and recombinant adenoviral vectors （Ad -GPR14- shRNA） were randomly administered by caudal intravenation to SHR or normotensive Wistar- Kyoto rats （WKY）. Expression of GPR14 protein levels in left ventricle and thoracic aorta and systolic blood pressure （SBP） of the caudal artery were measured 1 week before and the 0, 1,2, 3 and g week after caudal intravenation. Heart, thoracic aorta and superior mesenteric artery were collected at the 2nd weekend after caudal intravenation to analyze the ratio of left ventricular to body weight, cross - sectional areas of myocytes, myocardial fibrosis, media thickness and the media/lumen ratio of thoracic aorta and superior mesenteric artery. Results GPR14 protein levels at left ventricle and thoracic aorta and caudal artery pressure were significantly decreased in both SHR and WKY rats during the 1st to 4th week after caudal intravenation of Ad - GPR14 - shRNA. The decreased GPR14 protein and depressor effects reached their maximal effects at the 2nd week since Ad - GPR14 - shRNA intravenation. The changes were more significant in SHR than in WKY group. The ratio of left ventricular weight to body weight, cross - sectional areas of myocytes and myocardial fibrosis, media thickness and the media/lumen ratio of thoracic aorta and superior mesenteric artery significantly decreased at the 2nd week after Ad - GPR14 - shRNA treatment in SHR. Conclusion RNA interference targeting GPR14 gene significantly inhibited myocardial and thoracic aorta GPR14 expressions and played a prolonged antihypertensive effects and improved myocardial and vascular remodeling in SHR. The RNA interference for silencing of the GPR14 technology may be a potential available strategy of gene therapy for hypertension.