Department of Pharmacology and Nutritional Sciences, University of Kentucky , Lexington, Kentucky.
Attoquant Diagnostics, Vienna , Austria.
Am J Physiol Heart Circ Physiol. 2019 Mar 1;316(3):H506-H515. doi: 10.1152/ajpheart.00473.2018. Epub 2018 Dec 14.
Deletion of the prorenin receptor (PRR) in adipose tissue elevates systolic blood pressure (SBP) and the circulating soluble form of PRR (sPRR) in male mice fed a high-fat (HF) diet. However, sex differences in the contribution of adipose-PRR and sPRR to the regulation of the renin-angiotensin system (RAS) in key organs for blood pressure control are undefined. Therefore, we assessed blood pressure and the systemic and intrarenal RAS status in adipose-PRR knockout (KO) female mice. Blockade of RAS with losartan blunted SBP elevation in HF diet-fed adipose-PRR KO mice. ANG II levels were significantly increased in the renal cortex of HF diet-fed adipose-PRR KO female mice, but not systemically. HF diet-fed adipose-PRR KO mice exhibited higher vasopressin levels, water retention, and lower urine output than wild-type (WT) mice. The results also showed that deletion of adipose-PRR increased circulating sPRR and total hepatic sPRR contents, suggesting the liver as a major source of elevated plasma sPRR in adipose-PRR KO mice. To mimic the elevation of circulating sPRR and define the direct contribution of systemic sPRR to the regulation of the RAS and vasopressin, C57BL/6 female mice fed a standard diet were infused with recombinant sPRR. sPRR infusion increased plasma renin levels, renal and hepatic angiotensinogen expression, and vasopressin. Together, these results demonstrate that the deletion of adipose-PRR induced an elevation of SBP likely mediated by an intrarenal ANG II-dependent mechanism and that sPRR participates in RAS regulation and body fluid homeostasis via its capacity to activate the RAS and increase vasopressin levels. NEW & NOTEWORTHY The elevation of systolic blood pressure appears to be primarily mediated by cortical ANG II in high-fat diet-fed adipose-prorenin receptor knockout female mice. In addition, our data support a role for soluble prorenin receptor in renin-angiotensin system activation and vasopressin regulation.
脂肪组织中肾素原受体 (PRR) 的缺失会导致雄性高脂肪 (HF) 饮食喂养小鼠的收缩压 (SBP) 升高和循环可溶性 PRR (sPRR) 升高。然而,脂肪组织-PRR 和 sPRR 对控制血压的关键器官中肾素-血管紧张素系统 (RAS) 的调节的性别差异尚未确定。因此,我们评估了脂肪组织-PRR 敲除 (KO) 雌性小鼠的血压和全身及肾脏内 RAS 状态。用氯沙坦阻断 RAS 可使 HF 饮食喂养的脂肪组织-PRR KO 小鼠的 SBP 升高减弱。HF 饮食喂养的脂肪组织-PRR KO 雌性小鼠的肾皮质中 ANG II 水平显著升高,但全身系统中没有升高。HF 饮食喂养的脂肪组织-PRR KO 小鼠表现出比野生型 (WT) 小鼠更高的血管加压素水平、水潴留和更低的尿量。结果还表明,脂肪组织-PRR 的缺失增加了循环 sPRR 和总肝 sPRR 含量,提示肝脏是脂肪组织-PRR KO 小鼠中血浆 sPRR 升高的主要来源。为了模拟循环 sPRR 的升高并确定系统 sPRR 对 RAS 和血管加压素调节的直接贡献,用重组 sPRR 输注喂养标准饮食的 C57BL/6 雌性小鼠。sPRR 输注增加了血浆肾素水平、肾脏和肝脏血管紧张素原的表达以及血管加压素。综上所述,这些结果表明,脂肪组织-PRR 的缺失导致 SBP 升高,可能是通过肾内 ANG II 依赖性机制介导的,并且 sPRR 通过激活 RAS 和增加血管加压素水平参与 RAS 调节和体液稳态。
高脂肪饮食喂养的脂肪组织肾素原受体敲除雌性小鼠中,收缩压升高似乎主要是由皮质 ANG II 介导的。此外,我们的数据支持可溶性肾素原受体在肾素-血管紧张素系统激活和血管加压素调节中的作用。