Ovariectomy Causes Overexpression of Renal Na⁺,K⁺-ATPase and Sodium-Sensitive Hypertension in Adult Wistar Rats

Abstract

We investigated the effect of ovariectomy(oVx) on renal and systemic hemodynamic, electrolyte excretion and total and dephosphorylated Na⁺,K⁺-ATPase α1 subunit (t-d-NKA) in normotensive Wistar rats under a normal sodium (NS, 0.24%) or high sodium (HS, 1%) intake versus intact female (IF). On NS intake, t-d-NKA was higher in oVx rats and overexpressed in the thick ascending limbs (P < .01 vs. IF) and renal plasma flow was increased. On HS intake, oVx rats maintained a greater dephosphorylated NKA, excreted less sodium, and developed arterial hypertension (134 ± 4 vs. IF 112 ± 5 mm Hg, P < .05). Sodium load caused salt-sensitive hypertension in oVx Wistar rats.

• ovariectomy
• renal Na⁺
• K⁺-ATPase
• phospho state
• sodium-sensitive hypertension
• mTAL
• female hormones
• sodium excretion

ACKNOWLEDGMENTS

The authors thank Dr Marisa Vazquez, School of Nutrition, Faculty of Medicine, Buenos Aires University, for her helpful assistance in statistics. Part of this work was presented at the American Society of Nephrology Meeting, Philadelphia, November 8th, 2011.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

This work was supported by grants from Secretaría de Ciencia Y Tecnología, Buenos Aires University (UBACYT) and from Agencia Nacional de Promoción Científica y Tecnológica (ANPCYT).