两肾一夹高血压大鼠肾脏血管紧张素转换酶2的表达

Expression of angiotensin-converting enzyme 2 in hypertensive rat models

目的:观察两肾一夹(2K1C)高血压大鼠肾脏血管紧张素转换酶2(ACE2)蛋白和mRNA的表达。方法:30只雄性Wister大鼠随机分为2组,对照组和2K1C高血压组各15只。鼠尾容积法测定术前、术后1周、4周、8周的血压变化。8周后,免疫组化法检测肾脏ACE2蛋白表达,放射免疫分析法测定心肌组织AngⅡ水平,逆转录聚合酶链式反应(RT-PCR)法检测肾脏ACE2 mRNA表达。结果:①2K1C组术后血压明显高于术前和对照组(P<0.01);②与对照组相比,高血压模型组心肌局部AngⅡ浓度显著升高(P<0.01);③高血压模型组ACE2蛋白和mRNA表达较对照组明显降低(均P<0.05)。结论:2K1C高血压大鼠心肌局部AngⅡ浓度升高,肾脏组织ACE2蛋白和mRNA表达降低。

Objective ： To observe the expression of angiotensin-converting enzyme 2 （ACE2） protein and ACE2 mRNA in kidneys of the hypertensive rat models by using two-kidney and one-clip （2K1C） method. Methods ： Thirty adult male Wistar rats were randomized into groups of 2K1C hypertension and controls. The systolic blood pressure （SBP） was measured before operation, 1 week, 4 weeks and 8 weeks after operation, respectively, by tail-cuff method. Immaunohistochemical and RT-PCR technique were used to determine the distribution and expression of ACE2 protein and ACE2 mRNA in the kidneys, and the myocardial angiotensin Ⅱ level was measured by radioimmunoassay after 8 weeks. Results ： SBP in 2K1C group was significantly higher than that of the control group （ P 〈 0. 001 ）. The myocardial angiotensin level in 2K1C group increased remarkably as compared with the control group （ P 〈0.01） whereas the expression of ACE2 protein and ACE2 mRNA in the kidneys decreased significantly in 2K1C group （ P 〈 0.05 ）. Conclusion： The down-regulated ACE2 protein and ACE2 mRNA in the kidneys of 2K1C hypertensive animal models may be one of the mechanisms due to high blood pressure.