Objective To investigate the effect of angiotensin-converting enzyme (ACE) and angiotensin Ⅱtype 1 receptor (AT1R) on the blood pressure and kidney of spontaneously hypertensive rats (SHR) by RNA interfer-ence technique. Methods Ad5-ACE-shRNA treatment group; Ad5-AT1R-shRNA treatment group; SHR Ad5-ACE-AT1R was injected into the control group (injection control adenovirus), The recombinant adenovirus vector containing the short hairpin RNA (shRNA) expressing the ACE gene, the AT1R gene, the ACE and the AT1R gene, respectively, was injected with the WKY normal blood pressure control group (injection of saline). All the rats in each group were injected once on the first 17 days of the experiment, and the blood pressure and heart rate were measured before and after the intervention. The expression of ACE and AT1R mRNA was detected by real-time fluorescence quantitative PCR. The expression of ACE and AT1R protein was detected by Western blotting. At the end of the experiment, the renal tissue was examined by light microscopy and the ultrastructure of the kidney was observed by electron mi-croscopy. Results Ad5-ACE-shRNA treatment group; Ad5-AT1R-shRNA treatment group; SHR Ad5-ACE-AT1R-shRNA treatment group after each injection, tail artery pressure decreased by 24 mmHg (1 mmHg=0.133 kPa), 22 mmHg, 26 mmHg. The blood pressure of the SHR blank control group and the virus control group continued to in-crease by about 26 mmHg, and the difference between the two groups was not statistically significant (P>0.05). The blood pressure of the SHR blank control group and the virus control group were increased by about 26 mmHg, (Ad5-ACE-AT1R-shRNA) in the brain, aorta and kidney tissues of the WKY group (Ad5-AT1R-shRNA, Ad5-ACE1) (P<0.05). The expression of AT1R mRNA in brain, aorta and kidney tissues was significantly lower than that in blank control group (P<0.05), but there was no significant difference compared with WKY group. The expression of AT1R protein in renal tissue of SHR group was significantly lower than that of SHR control group and SHR virus control group (P<0.05). Electron microscopic observation showed that the ultrastructure of renal cell in treatment group was improved obviously. Conclusion RNA interference can down-regulate the expression of ACE and AT1R, reduce spontaneous hypertensive rats and improve renal injury, especially Ad5-ACE-AT1R-shRNA treatment group has obvi-ous effect and less side effect. RNA interference has a good prospect for gene therapy of hypertension.%目的 用RNA干扰下调血管紧张素转换酶(ACE)和血管紧张素Ⅱ1型受体(AT1R),观察其对自发性高血压大鼠(SHR)血压及肾脏的影响.方法 SHR随机分为5组:即空白对照组(注射0.9%氯化钠注射液);病毒对照组(注射对照腺病毒);Ad5-AT1R-shRNA治疗组;Ad5-ACE-shRNA治疗组;SHR 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0.9%氯化钠注射液).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检测肾脏ACE和AT1R mRNA的表达;用蛋白质印迹法检测肾脏ACE和AT1R蛋白的表达.实验结束时做肾脏组织光镜病理检查.结果 Ad5-AT1R-shRNA治疗组;Ad5-ACE-shRNA治疗组;SHR Ad5-ACE-AT1R-shRNA治疗组于每次注射后,尾动脉压分别下降达24 mmHg(1 mmHg=0.133 kPa)、22 mmHg、26 mmHg左右,单次注射后降压作用至少可持续15 d左右,累计降压幅度分别达39 mmHg、37 mmHg、43 mmHg;SHR空白对照组和病毒对照组血压则持续升高约26 mmHg,且2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-AT1R-shRNA、Ad5-ACE-shRNA)肾脏组织中的ACEmRNA和治疗组(Ad5-AT1R-shRNA、Ad5-ACE-AT1R-shRNA)肾脏组织中的AT1R mRNA的表达明显低于空白对照组、病毒对照组(P<0.05),而与WKY组比较差异无统计学意义.SHR治疗组肾脏组织的AT1R蛋白表达均较SHR空白对照组、SHR病毒对照组显著降低,差异有统计学意义(P<0.05);观察显示治疗组肾脏细胞结构明显改善.结论 RNA干扰下调ACE和AT1R表达,降低自发性高血压大鼠血压并改善肾脏损伤,尤以Ad5-ACE-AT1R-shRNA治疗组效果明显而且副作用少.RNA干扰对高血压的基因治疗具有良好应用前景.
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