性别与雌激素水平对肾血管性高血压大鼠肾素-血管紧张素系统组分蛋白和基因表达的影响

Effect of the gender and estrogen disparities on the mRNA and protein expressions of components of renin-angiotensin-system in renovascular hypertensive rats

目的研究性别和雌激素水平在肾血管性高血压(RVH)大鼠肾组织中血管紧张素转换酶2(ACE2)-血管紧张素1-7(Ang 1-7)-Mas轴的差异。方法用10周龄SD大鼠制备两肾一夹RVH模型。将造模成功大鼠分为3组:雄性手术组、雌性手术组和雌性手术去势组,每组10只。术后32周,用酶联免疫吸附法测定肾组织中Ang1-7含量;用实时荧光定量-PCR和蛋白质印迹法分别检测肾组织中ACE2、血管紧张素Ⅱ的1a和1b型受体(AT1aR和AT1bR)和Mas的基因和蛋白的表达水平。结果雌性手术组、雄性手术组和雌性手术去势组的Ang1-7的含量分别为(17.14±7.87),(46.47±11.94)和(37.26±9.08)pg·mL^-1;这3组的AT1aR基因的相对表达量分别为3.16±0.75,1.00±0.08和0.88±0.09;这3组的AT1bR基因的相对表达量分别为3.34±0.42,1.00±0.08和1.09±0.11;这3组的ACE2基因的相对表达量分别为0.44±0.08,1.00±0.05和0.84±0.08;这3组的的Mas基因的相对表达量分别为0.56±0.09,1.00±0.05和1.04±0.10。雌性手术组与雄性手术组和雌性手术去势组比较,上述指标的差异均有统计学意义(均P<0.05)。蛋白结果的趋势与基因一致。结论肾组织中Ang1-7含量、ACE2和Mas的基因和蛋白表达存在性别与雌激素水平差异性;雌激素可上调AT1aR、AT1bR和ACE2的基因和蛋白表达,从而降低ACE2-Ang1-7-Mas轴的活性。

Objective to investigate the difference of the gender disparities and estrogen levels on angiotensin-converting enzyme 2(ACE2)-angiotensin 1-7(Ang 1-7)-Mas axis in the renal tissue of renovascular hypertension(RVH)rats.Methods Ten weeks old Sprague-Dawley(SD)rats were adopted to formulate a two-kidney one-clip model of renovascular hypertension,which includes the following three groups:female surgery group,male surgery group and female surgical castration group,each group had 10 rats.At 32 weeks after surgery,the level of renal angiotensin 1-7(Ang 1-7)were determined by enzyme linked immunosorbent assay.Protein and mRNA expression levels of ACE2,angiotensin type 1 a receptor(AT1 aR),angiotensin type 1 b receptor(AT1 bR)and Mas in renal tissue were detected by Western blot and real time fluorescence quantitative-PCR,respectively.Results Ang1-7 content in female surgery group,male surgery group and female surgical castration group were(17.14±7.87),(46.47±11.94),(37.26±9.08)pg·mL-1,respectively;the relative expression levels of AT1 aR mRNA in the above three groups were 3.16±0.75,1.00±0.08,0.88±0.09,respectively;the relative expression levels of AT1 bR mRNA in the above three groups were 3.34±0.42,1.00±0.08,1.09±0.11;the relative expression levels of ACE2 mRNA in the above three groups were 0.44±0.08,1.00±0.05,0.84±0.08,respectively;the relative expression levels of Mas mRNA in the above three groups were 0.56±0.09,1.00±0.05,1.04±0.10;comparison between female surgery group,male surgery group and female surgical castration group,the difference of the factors were significantly(all P<0.05).The trend of protein results is consistent with that of gene.Conclusion Gender and estrogen disparities would lead to various contents of Ang 1-7 and the mRNA and protein expressions of ACE2 and Mas in renal tissue.Estrogen up-regulates the mRNA and protein expression of AT1 a R,AT1 bR,ACE1 and reduces the activity of ACE2-Ang1-7-Mas axis.