小鼠止血带休克后肾组织ACE/ACE2表达变化及意义

目的: 通过观察小鼠止血带休克(TS)后,不同时点血管紧张素转换酶(ACE)和血管紧张素转换酶2(ACE2)在肾脏的表达变化与肾损伤程度的关系,探讨ACE/ACE2表达失衡在TS后肾损伤中的作用。方法: 复制小鼠TS模型,Western blotting测肢体缺血再灌注后12 h内肾组织ACE和ACE2蛋白的表达;利用化学比色方法测定血清和肾组织丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性;制作肾病理切片,观察肾组织形态变化,并利用免疫组织化学方法观察ACE和ACE2的表达部位。结果: Western blotting结果显示,各时点与对照组比较,TS后ACE表达升高,ACE2表达降低;与对照组比较血清和肾MDA水平增高(P<0.05),SOD活性降低(P<0.05);HE病理切片显示,TS后各时点肾组织有充血、炎细胞浸润等不同程度损伤;免疫组化结果显示,ACE在肾小管上皮细胞胞浆表达,TS后表达明显增强;ACE2主要在肾小管上皮细胞管腔膜表达,TS后表达明显降低。结论: TS后肾组织ACE表达升高,ACE2表达降低,ACE/ACE2表达失衡可能与肾损伤有关。     

ACE2基因敲除小鼠止血带休克后肾组织ACE/AngⅡ表达的变化及其与肾损伤的关系

 目的： 通过观察血管紧张素转换酶2(ACE2)基因敲除(KO)小鼠止血带休克(TS)后肾组织血管紧张素转化酶/血管紧张素Ⅱ（ACE/AngⅡ）的表达及损伤程度的变化,探讨ACE2在休克后急性肾损伤中的作用。方法： 小鼠双下肢用止血带结扎缺血2 h、松带后再灌注4 h复制TS模型。将雄性6月龄野生型（WT）C57BL/6小鼠和相同背景的ACE2 KO小鼠各12只分为4组,即WT组、WT+TS组、KO组和KO+TS组,每组6只。Western blotting测肾组织ACE蛋白的表达;ELISA法测定肾组织AngⅡ表达;利用化学比色方法测定肾组织丙二醛（MDA）含量、超氧化物歧化酶（SOD）活性、血尿素氮（BUN）和血清肌酐（Cr）含量。结果： 与WT小鼠相比,WT+TS小鼠肾组织ACE/AngⅡ表达明显增加,出现肾组织氧化应激损伤和功能改变;与WT小鼠相比,KO小鼠肾组织ACE/AngⅡ表达增加,但未见明显的氧化应激损伤和功能变化;与WT+TS小鼠相比,KO+TS小鼠肾ACE/AngⅡ表达进一步增加,肾组织氧化应激和肾功能损伤明显加重。结论： ACE2基因缺失可能通过增加ACE/AngⅡ表达加重止血带休克肾的氧化应激损伤,针对ACE2靶f点的药物有可能成为防治止血带休克时急性肾损伤的策略之一。     

血管紧张素转换酶2在自发性高血压大鼠肾脏表达与血压的关系研究

目的： 研究血管紧张素转换酶2(ACE2)在20周龄自发性高血压大鼠(SHR)和Wistar Kyoto大鼠(WKY)肾脏组织的表达以及与血压的关系。 方法： 采用实时定量PCR方法检测肾脏组织中ACE2 mRNA的含量，应用放免法测定肾脏组织血管紧张素Ⅱ(AngⅡ)的浓度。 结果： 20周龄SHR的血压明显高于WKY（P<0.05）,SHR肾脏组织ACE2的表达显著低于WKY（P<0.01），而SHR肾脏组织AngⅡ的浓度显著高于WKY（P<0.05）。 结论： ACE2在肾素-血管紧张素系统(RAS)中可能通过改变SHR肾脏中AngⅡ水平调节血压。     

脑内ACE2基因过表达对高血压前期大鼠血压进展和氧化应激的影响

目的:观察下丘脑室旁核内血管紧张素转换酶2(angiotension-converting enzyme 2,ACE2)基因过表达对高血压前期大鼠血压进展和中枢氧化应激的影响,并探讨ACE2基因中枢降压的分子机制。方法:ACE2基因以慢病毒为载体,载体上携带增强型绿色荧光蛋白(enhanced green fluorescent protein,eGFP),由上海吉凯基因化学技术有限公司构建。对6周龄雄性自发性高血压大鼠(spontaneously hypertensive rats,SHR)进行2周跑台运动,随后随机分成SHR组、ACE2基因过表达(SHR-ACE2)组和病毒载体(SHR-eGFP)组,每组10只,同时选取10只血压正常的Wistar-Kyoto(WKY)大鼠不进行任何干预,作为对照组。将ACE2基因和病毒载体分别注射到8周龄SHR的下丘脑室旁核。每4周测1次血压,8周后测定动脉压力反射敏感性(baroreflex sensitivity,BRS),以及血浆去甲肾上腺素(norepinephrine,NE)和室旁核血管紧张素Ⅱ(angiotensin Ⅱ,Ang Ⅱ)水平;二氢乙啶(dihydroethidium,DHE)染色法检测室旁核活性氧(reactive oxygen species,ROS)水平;Western blot检测室旁核ACE2和NADPH氧化酶(NADPH oxidase,NOX)的蛋白表达。结果:SHR组和SHR-eGFP组室旁核ACE2蛋白表达显著低于WKY组(P<0.01),而SHR-ACE2组ACE2蛋白表达显著高于SHR组(P<0.05),且与WKY组相比无显著差异。与WKY组相比,SHR组和SHR-eGFP组收缩压显著升高,伴有BRS显著降低(P<0.01),而SHR-ACE2组收缩压较SHR组降低(P<0.01),高血压前期进展延缓,且BRS提高(P<0.01)。SHR组和SHR-eGFP组血浆NE浓度、室旁核Ang Ⅱ和ROS水平及NOX2和NOX4蛋白表达均高于WKY组(P<0.01),而ACE2基因过表达显著逆转上述变化(P<0.05)。结论:SHR室旁核过表达ACE2基因能延缓高血压前期进展,改善动脉血压调节,并抑制交感神经活动,其机制可能与降低脑内Ang Ⅱ水平,减轻中枢氧化应激有关。     

失血性休克后肠淋巴液引流恢复小鼠肾组织ACE/ACE2平衡的作用

目的:观察失血性休克后肠淋巴液(PHSML)引流对失血性休克小鼠肾组织血管紧张素转换酶(ACE)/ACE2平衡的作用。方法:复制小鼠失血性休克模型,随机分为休克组与休克+引流组,行液体复苏;休克+引流组液体复苏后,引流肠淋巴液。在液体复苏后6 h,检测肾组织ACE、ACE2、血管紧张素II(Ang II)1型受体(AT1R)、Mas相关G蛋白偶联受体(MasR)的mRNA表达以及Ang II、Ang(1-7)含量。结果:失血性休克提高了肾组织ACE mRNA、AT1R mRNA和Ang II水平,降低了ACE2 mRNA、MasR mRNA和Ang(1-7)水平,PHSML引流抑制了失血性休克对ACE2和AT1R mRNA表达的影响;同时PHSML引流也降低了失血性休克增加ACE/ACE2、Ang II/Ang(1-7)和AT1R/MasR比值的作用。结论:PHSML引流恢复了失血性休克后肾组织的ACE/ACE2平衡,有利于减轻失血性休克所致的肾损伤。     

ACE2内源性激动剂DIZE对糖尿病肾病大鼠的保护作用

目的:观察血管紧张素转换酶2(ACE2)内源性激动剂乙酰甘氨酸重氮氨苯脒(DIZE)对糖尿病肾病(DN)大鼠的保护作用。方法:30只Wistar大鼠随机分为正常对照组(NC组)、DN组和DIZE处理组(DIZE组)。DN组与DIZE组一次性腹腔注射链脲佐菌素(65 mg/kg)建立糖尿病模型,12周后糖尿病肾病大鼠模型建立后给予DIZE 15 mg·kg~(-1)·d~(-1)或等量生理盐水皮下注射4周处理。16周末称量体重和肾重,计算肾质量体质量比(KW/BW),收集血、尿标本,检测血糖(GLU)、24 h尿蛋白(24UP)及血清肌酐(SCr)等指标。通过PAS染色观察各组肾脏病理变化;ELISA法检测大鼠AngⅡ、Ang-(1-7)、TGF-β1及VCAM-1水平的变化;通过免疫组化观察collagenⅠ和FN蛋白表达的变化;利用实时荧光定量PCR(RT-qPCR)技术检测大鼠肾组织collagenⅠ和FN mRNA含量的变化;Western blot观察各组大鼠ACE2蛋白表达的变化。结果:DIZE显著提高了糖尿病大鼠ACE2的表达(P0.05),降低了糖尿病大鼠血浆AngⅡ含量(P0.05),提高了Ang-(1-7)的水平(P0.05)。与NC组大鼠相比,DN组与DIZE组大鼠的24UP、SCr和KW/BW明显升高(P0.05),collagenⅠ和FN mRNA水平及蛋白表达量增加,肾脏组织TGF-β1及VCAM-1明显上升(P0.05)。DIZE组与DN组大鼠相比,24UP和SCr水平降低(P0.05),GLU和KW/BW无明显差异,collagenⅠ和FN mRNA含量及蛋白表达量减少,肾脏组织TGF-β1及VCAM-1水平降低(P0.05)。结论:ACE2内源性激动剂DIZE显著提高了ACE2的活性,增加了Ang-(1-7)的含量,从而降低了肾脏纤维化及炎症水平,并对糖尿病肾病大鼠起到保护性作用。     

脓毒症诱导的急性呼吸窘迫综合征与肾素-血管紧张素系统

目的 研究脓毒症诱导的急性呼吸窘迫综合征(ARDS)与肾素-血管紧张索系统(RAS)的关系及其机制.方法 雄性BALB/c小鼠60只随机分3组(n=20):正常对照组,假手术组,手术组.应用盲肠结扎穿孔术(CLP)诱导ARDS动物模型,采用术后18 h小鼠动脉血气分析、肺湿干质量比(W/D)和肺组织病理等作为肺损伤指标;并在术后6 h检测血管紧张素转化酶(ACE)、ACE2及血管紧张素Ⅱ(AngⅡ)的变化.结果 术后18 h手术组较假手术组小鼠肺水明显增多(W/D:6.08±0.64比4.38±0.93,P<0.01),缺氧加重[PaO2:(40.80±5.03)mm Hg比(72.80±4.32)mm Hg,P<0.01],氧合指数明显下降(PaO2/FiO2:194.30±23.90比346.70±20.50,P<0.01),且肺病理显示手术组小鼠肺出现明显的炎性细胞渗出、肺水肿和间隔增厚等改变.术后6 h手术组小鼠肺组织和血中AngⅡ表达量较假手术组明显升高(P<0.01).免疫组织化学显示假手术组和手术组小鼠肺组织中血管壁可见明显的ACE表达,手术组肺组织ACE2表达较其他2组弱.结论 脓毒症诱导的ARDS存在RAS系统激活,其中Ang Ⅱ表达增加可能加重肺损伤,而ACE2减少可能是AngⅡ增高的原因.     

ACE2在高血压大鼠左心室重构中的作用及缬沙坦干预的作用

目的观察血管紧张素转换酶2(ACE2)在自发性高血压大鼠(SHR)左心室中的表达以及缬沙坦干预后对ACE2表达水平的影响。方法 24只12周龄雄性SHR随机分为SHR组、缬沙坦组,12只同龄雄性血压正常的Wistar大鼠作为正常对照组。10周后处死,测定心脏重量指数(HWI)、左心室重量指数(LVWI);酶联免疫法测定血浆中AngⅡ的浓度;碱水解法测定心肌中羟脯氨酸的含量;反转录-聚合酶链反应检测心肌中ACE2的表达。结果与正常对照组比较,SHR组LVWI、血浆中AngⅡ的浓度以及心肌羟脯氨酸的含量均增高(P<0.05),心肌组织中ACE2的表达显著降低(P<0.05);与SHR组比较,缬沙坦组LVWI、血浆中AngⅡ的浓度以及心肌羟脯氨酸的含量均降低(P<0.05),心肌组织中ACE2表达显著增高(P<0.05)。结论缬沙坦可逆转高血压左心室重构,机制可能与增加心肌中ACE2的表达有关。     

依那普利对自发性高血压大鼠心肌ACE和ACE2表达的影响

 目的 观察自发性高血压大鼠(spontaneously hypertensive rats, SHR)心肌的血管紧张素转换酶(angiotensin-converting enzyme, ACE)和ACE2的表达,以及依那普利干预的影响。方法 将15只SHR随机分为2组：SHR对照组(n=7)和依那普利组(n=8),分别给以安慰剂、依那普利15mg.kg-1.d-1灌胃干预4周。干预结束后处死大鼠,分离左心室,行RT-PCR、western blot蛋白质免疫印迹检测。同步取10只WKY大鼠作为正常血压对照组。结果SHR心肌的ACE的mRNA和蛋白质的表达都显著高于)WKY组(1.68±0.34 vs 0.33±0.12, P＜0.05;1.21±0.14 vs 0.71±0.11, P＜0.05),而ACE2 的mRNA和蛋白质表达皆明显低于WKY组(0.50±0.15 vs 1.16±0.24, P＜0.05; 0.71±0.24 vs 1.22±0.14, P＜0.05)。依那普利明显降低ACE的mRNA和蛋白质表达(0.44±0.19 vs 1.68±0.34, P＜0.01; 0.87±0.13 vs 1.21±0.14, P＜0.05),提升ACE2的mRNA表达(1.77±0.49 vs 0.50±0.15, P＜0.05),对ACE2的蛋白表达无明显影响(0.42±0.22 vs 0.71±0.24, P＞0.05)。结论 SHR心肌ACE明显升高,ACE2显著降低,有利于血压上调。依那普利能降低ACE,提升ACE2,可能是血管紧张素转换酶抑制剂(angiotensin-converting enzyme inhibitors, ACEI)的降压机制之一。     

血管紧张素转换酶和血管紧张素原基因多态性及其与青海妊娠高血压疾病的相关性

目的探讨血管紧张素转换酶(ACE)和血管紧张素原(AGT)基因表达、基因多态性与青海孕产妇妊娠高血压疾病的相关性。方法选择210例妊娠高血压患者(HDCP组)和220例正常孕妇(CK组),运用限制性内切酶片段长度多态性聚合酶链反应(PCR-RFLP)方法检测AGT M235T、ACE I/D基因多态性。结果CK组ACE基因DD、ID、Ⅱ所占比例分别为28.18%、47.73%、24.09%,HDCP组分别为33.81%、51.90%、14.29%(P<0.05,故两组的ACE基因分布有差异),HDCP组和对照组ACE I/D多态性等位基因I和D频率分布有差异(P<0.05),HDCP组D等位基因频率高于对照组(χ^2=5.188,P<0.05),ACE基因型分布符合Hardy-Weinberg遗传平衡(χ^2=0.423,df=2,查表χ^2界值表,P>0.05,达到遗传平衡);CK组AGT基因MM、MT、TT所占比例分别为24.09%、43.64%、32.27%,HDCP组分别为15.71%、42.86%、41.43%(P<0.05,故两组的AGT基因分布差异有统计学意义),HDCP组和对照组AGT M235T多态性等位基因M和T频率分布有差异性(P<0.05),HDCP组T等位基因频率高于对照组(χ^2=6.796,P<0.05),AGT基因型分布符合Hardy-Weinberg遗传平衡(χ^2=3.242,df=2,查表χ^2界值表,P>0.05,达到遗传平衡)。结论ACE I/D多态性和AGT M235T多态性与青海省汉族妊娠期高血压疾病有关,D等位基因和T等位基因可能是妊娠高血压疾病的易感基因。     

Angiotensin II up-regulates angiotensin I-converting enzyme (ACE), but down-regulates ACE2 via the AT1-ERK/p38 MAP kinase pathway

The recent discovery of the angiotensin II (Ang II)-breakdown enzyme, angiotensin I converting enzyme (ACE) 2, suggests the importance of Ang II degradation in hypertension. The present study explored the signaling mechanism by which ACE2 is regulated under hypertensive conditions. Real-time PCR and immunohistochemistry showed that ACE2 mRNA and protein expression levels were high, whereas ACE expression levels were moderate in both normal kidney and heart. In contrast, patients with hypertension showed marked ACE up-regulation and ACE2 down-regulation in both hypertensive cardiopathy and, particularly, hypertensive nephropathy. The inhibition of ACE2 expression was shown to be associated with ACE up-regulation and activation of extracellular regulated (ERK)1/2 and p38 mitogen-activated protein (MAP) kinases. In vitro, Ang II was able to up-regulate ACE and down-regulate ACE2 in human kidney tubular cells, which were blocked by an angiotensin II (AT)1 receptor antagonist (losartan), but not by an AT2 receptor blocker (PD123319). Furthermore, blockade of ERK1/2 or p38 MAP kinases by either specific inhibitors or a dominant-negative adenovirus was able to abolish Ang II-induced ACE2 down-regulation in human kidney tubular cells. In conclusion, Ang II is able to up-regulate ACE and down-regulate ACE2 expression levels under hypertensive conditions both in vivo and in vitro. The AT1 receptor-mediated ERK/p38 MAP kinase signaling pathway may be a key mechanism by which Ang II down-regulates ACE2 expression, implicating an ACE/ACE2 imbalance in hypertensive cardiovascular and renal damage.     

双肾双夹易卒中型肾血管性高血压大鼠重要靶器官ACE2表达研究

目的： 本实验观察在肾性高血压的发生发展过程中大鼠重要靶器官脑、心肌、肾、主动脉组织中血管紧张素I转化酶2（ACE2）的表达变化情况，探讨在高血压的发生发展过程中ACE2的变化规律，为防治高血压提供新的研究作用靶点。方法: 建立双肾双夹易卒中型肾血管性高血压大鼠动物模型，用Western blotting的方法研究在高血压发生发展过程中重要靶器官组织中ACE2的表达。 结果: 2周末高血压组血压明显升高，4周末高血压组心脏体重比明显升高，高血压组重要靶器官心、脑、肾、主动脉中ACE2的表达随高血压的时程发展明显减少。结论: 双肾双夹易卒中型肾血管性高血压大鼠重要靶器官组织中ACE2表达减少，提示ACE2参与高血压的发生发展，并与高血压靶器官的损害有关。     

Interstitial fibroblast-like cells express renin-angiotensin system components in a fibrosing murine kidney

Recently, the renin-angiotensin system (RAS) was implicated in organ fibrosis. However, few studies have examined the localization of RAS components, such as angiotensin II receptors, renin (REN), angiotensinogen (AGTN), and angiotensin-converting enzyme (ACE), in the fibrosing kidney. To localize these components in the fibrosing kidney, we used a murine model of renal fibrosis that shows an enhanced expression of angiotensin II type 1A receptor (AT(1A)R) and AGTN. Our results indicate that the overall expression of angiotensin II type 2 receptor (AT(2)R) and ACE was attenuated in this model, whereas REN expression was unchanged. In addition to tubular epithelial cells that were positive for AT(1A)R, AT(2)R, REN, and AGTN, interstitial fibroblast-like cells expressed AT(1A)R, REN, AGTN, and ACE in the fibrosing kidney. The interstitial fibroblast-like cells that were positive for AT(1A)R mRNA were further characterized as positive for the expression of vimentin and transforming growth factor-beta1. These data provide strong evidence for a tubulointerstitial RAS within the fibrosing kidney, and a linkage between the RAS and renal fibrogenesis.     

Renal ACE2 expression in human kidney disease

Angiotensin-converting enzyme 2 (ACE2) is a recently discovered homologue of angiotensin-converting enzyme (ACE) that is thought to counterbalance ACE. ACE2 cleaves angiotensin I and angiotensin II into the inactive angiotensin 1-9, and the vasodilator and anti-proliferative angiotensin 1-7, respectively. ACE2 is known to be present in human kidney, but no data on renal disease are available to date. Renal biopsies from 58 patients with diverse primary and secondary renal diseases were studied (hypertensive nephropathy n = 5, IgA glomerulopathy n = 8, minimal change nephropathy n = 7, diabetic nephropathy n = 8, focal glomerulosclerosis n = 5, vasculitis n = 7, and membranous glomerulopathy n = 18) in addition to 17 renal transplants and 18 samples from normal renal tissue. Immunohistochemical staining for ACE2 was scored semi-quantitatively. In control kidneys, ACE2 was present in tubular and glomerular epithelium and in vascular smooth muscle cells and the endothelium of interlobular arteries. In all primary and secondary renal diseases, and renal transplants, neo-expression of ACE2 was found in glomerular and peritubular capillary endothelium. There were no differences between the various renal disorders, or between acute and chronic rejection and control transplants. ACE inhibitor treatment did not alter ACE2 expression. In primary and secondary renal disease, and in transplanted kidneys, neo-expression of ACE2 occurs in glomerular and peritubular capillary endothelium. Further studies should elucidate the possible protective mechanisms involved in the de novo expression of ACE2 in renal disease.     

氧化应激促进AGT-REN双转基因高血压小鼠心肌中电导钙激活钾离子通道表达

 目的:探讨心肌重构过程中心肌中电导钙激活钾离子通道(K_Ca3.1)蛋白表达与氧化应激反应之间的关系。方法:雄性血管紧张素-肾素(AGT-REN)双转基因高血压(dTH)小鼠2、4、8、12月龄各6只进行相应指标检测。另取12只6月龄雄性dTH小鼠,随机分为2组:模型组(dTH组)和N-乙酰半胱氨酸(NAC)组。同时取6只dTH同品系野生C57B6小鼠作为对照(WT组)。NAC组小鼠腹腔注射NAC 400 mg·kg^-1·d^-1,WT和dTH组小鼠腹腔注射等量生理盐水。4周后检测各组小鼠血压变化;ELISA法测定小鼠血浆中AngⅡ和Ang(1-7)含量变化;试剂盒检测心肌组织超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量;Western blot法检测小鼠心肌胶原蛋白collagen I、collagen III及K_Ca3.1蛋白表达的变化。结果:dTH组小鼠血压、血浆AngⅡ、MDA及胶原蛋白含量均高于同龄WT组小鼠(2月龄除外),并随年龄增长而增高(P<0.05);血浆Ang(1-7)和心肌SOD活性随年龄增长下降,并低于同龄WT组小鼠(2月龄除外)(P<0.05)。NAC干预使6月龄dTH小鼠心肌SOD活性增强(P<0.01),同时心肌MDA、胶原蛋白和K_Ca3.1蛋白表达下降(P<0.05)。结论:高血压所致心肌重构过程中心肌K_Ca3.1蛋白表达增加可能与心肌氧化应激水平增强有关。     

Netrin-1 overexpression in kidney proximal tubular epithelium ameliorates cisplatin nephrotoxicity

Netrin-1, a multifunctional laminin-related protein is widely expressed in various tissues, including kidney. The pathophysiological roles of netrin-1 in toxic acute kidney injury are unknown. To determine the role of netrin-1 in cisplatin-induced nephrotoxicity, we used netrin-1 transgenic mice that overexpress netrin-1 in the proximal tubular epithelium using the fatty acid binding protein promoter. Administration of cisplatin caused severe renal injury in WT mice but not in netrin-1 transgenic mice. Functional improvement was associated with better preservation of morphology, reduced cytokine expression and oxidative stress in the kidney, and reduced serum and urine cytokine and chemokine levels of transgenic mice as compared with WT mice. Cisplatin induced an increase in neutrophil infiltration into the kidney of WT mice, which was not significantly reduced in netrin-1 transgenic mice. Interestingly, ischemia reperfusion induced a large increase in apoptosis in WT mice but not in netrin-1 transgenic mice (215 ± 40 vs 94 ± 20 cells/5 HPF ( × 400), P < 0.0001), which was associated with reduced caspase-3 and p53 activation in the transgenic kidney. These results suggest that netrin-1 protects renal tubular epithelial cells against cisplatin-induced kidney injury by suppressing apoptosis and inflammation.     

Role of angiotensin-converting enzyme 2 and angiotensin(1-7) in 17beta-oestradiol regulation of renal pathology in renal wrap hypertension in rats

17beta-Oestradiol (E2)-mediated inhibition of angiotensin-converting enzyme (ACE) protects the E2-replete kidney from the progression of hypertensive renal disease. Angiotensin-converting enzyme 2 (ACE2), a homologue of ACE, counters the actions of ACE by catalysing the conversion of angiotensin II (Ang II) to angiotensin(1-7) [Ang(1-7)]. We investigated E2 regulation of ACE2 in the renal wrap (RW) model of hypertension in rats. After 6 weeks on a high-sodium diet (4% NaCl), the activity of ACE2 was reduced in the renal cortex by 31%, which was mirrored by similar decreases in ACE2 protein (30%) and mRNA expression (36%) in the ovariectomized RW rat (RW-OVX); E2 replacement prevented these effects. The RW-OVX rats exhibited greater renal injury, including 1.7-fold more tubulointerstitial fibrosis and 1.6-fold more glomerulosclerosis than E2-replete females (RW-Intact and RW-OVX+E2). Angiotensin(1-7) infusion prevented these exacerbating effects of ovariectomy on renal pathology; no differences in indicators of renal injury were observed between RW-OVX-Ang(1-7) and RW-Intact rats. These renal protective effects of Ang(1-7) infusion were not attributable to increased ACE2 activity or to changes in heart rate or body weight, since these parameters were unchanged by Ang(1-7) infusion. Furthermore, Ang(1-7) infusion did not attenuate renal injury by reducing mean arterial pressure (MAP), since infusion of the peptide did not lower MAP but rather caused a slight increase during a 6 week chronic treatment for Ang(1-7). These results suggest that E2-mediated upregulation of renal ACE2 and the consequent increased Ang(1-7) production contribute to E2-mediated protection from hypertensive renal disease. These findings have implications for E2-deficient women with hypertensive renal disease and suggest that therapeutics targeted towards increasing ACE2 activity and Ang(1-7) levels will be renal protective.