Department of Physiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia.
Department of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
Exp Biol Med (Maywood). 2023 Oct;248(20):1768-1779. doi: 10.1177/15353702231198085. Epub 2023 Oct 12.
An increase in blood pressure by a high-salt (HS) diet may change the expression levels of renal epithelial sodium channels (ENaCs) and aquaporins (AQPs). Spontaneously hypertensive rats (SHRs) and Wistar Kyoto (WKY) rats were exposed to HS and regular-salt (RS) diets for 6 weeks. Mean arterial pressure (MAP) and plasma atrial natriuretic peptide (ANP), angiotensin II (Ang II), aldosterone, and arginine vasopressin (AVP) levels were determined. Expression of mRNA levels of ENaCs and AQPs were quantified by real-time PCR. The MAP was higher in SHRs on the HS diet. Plasma Ang II and aldosterone levels were low while plasma ANP level was high in both strains of rats. Renal expression of mRNA levels of α-, β-, and γ-ENaCs was lowered in SHRs on the HS diet. Meanwhile, renal AQP1, AQP2, and AQP7 mRNA expression levels were lowered in both strains of rats on the HS diet. Suppression of mRNA expression levels of ENaC and AQP subunits suggests that the high-salt-induced increase in the MAP of SHR may not be solely due to renal sodium and water retention.
高盐（HS）饮食引起的血压升高可能会改变肾脏上皮钠通道（ENaC）和水通道蛋白（AQP）的表达水平。将自发性高血压大鼠（SHR）和 Wistar Kyoto（WKY）大鼠分别暴露于 HS 和 RS 饮食 6 周。测定平均动脉压（MAP）和血浆心钠肽（ANP）、血管紧张素 II（Ang II）、醛固酮和精氨酸加压素（AVP）水平。通过实时 PCR 定量测定 ENaC 和 AQP 的 mRNA 水平。HS 饮食的 SHR 的 MAP 更高。两种大鼠的血浆 Ang II 和醛固酮水平较低，而血浆 ANP 水平较高。HS 饮食下调 SHR 的 ENaCα、β 和γ亚基的 mRNA 水平。同时，两种大鼠的 HS 饮食下调肾脏 AQP1、AQP2 和 AQP7 的 mRNA 表达水平。ENaC 和 AQP 亚基的 mRNA 表达水平受到抑制，表明 SHR 高盐引起的 MAP 升高可能不仅仅是由于肾脏钠水潴留所致。
