Endothelin ETB receptors contribute to sex differences in blood pressure elevation in angiotensin II hypertensive rats on a high‐salt diet1. (28th May 2013)

• Record Type: Journal Article
• Authors: Kittikulsuth, Wararat; Looney, Stephen W; Pollock, David M
• Is Part Of: Clinical and experimental pharmacology and physiology. Volume 40:Number 6(2013:Jun.)
• Page Start: 362
• Page End: 370
• Publication Date: 2013-05-28
• Subjects: Clinical pharmacology -- Periodicals; Pharmacology, Experimental -- Periodicals; Physiology, Experimental -- Periodicals; Physiology, Pathological -- Periodicals; 615.1
• DOI: 10.1111/1440-1681.12084
• Languages: English
• ISSNs: 0305-1870

Abstract

<abstract abstract-type="main" id="cep12084-abs-0001"> <title>Summary</title> <p> <list id="cep12084-list-0001" list-type="order"> <list-item> <p>Female rats are more resistant to blood pressure increases induced by high salt (HS) intake or angiotensin (Ang) II infusion. Because endothelin ET<sub>B</sub> receptors on endothelial and epithelial cells mediate tonic vasodilation and sodium excretion, we hypothesized that ET<sub>B</sub> receptors limit the hypertensive response and renal injury induced by HS diet alone or with chronic AngII infusion (AngII/HS) in female compared with male rats.</p> </list-item> <list-item> <p>A 4 week HS diet (4% NaCl) did not significantly change blood pressure (measured by telemetry) in either male or female Sprague‐Dawley rats. Administration of the ET<sub>B</sub> receptor antagonist A‐192621 (1, 3 and 10 mg/kg per day in food) during HS feeding caused a dose‐dependent increase in blood pressure in both sexes.</p> </list-item> <list-item> <p>In AngII/HS rats, males had a larger increase in blood pressure than females. The increase in blood pressure produced by ET<sub>B</sub> receptor blockade in male AngII/HS rats was not significant. However, A‐192621 treatment resulted in a significant further increase in blood pressure in female AngII/HS rats. Male rats had consistently higher protein excretion rates before and during AngII/HS, but this was not significantly affected by ET<sub>B</sub> receptor blockade in either sex.</p> </list-item> <list-item> <p>In conclusion, ET<sub>B</sub> receptors play a significantly greater beneficial role in protecting female compared with male rats against AngII‐induced hypertension and may contribute to the sex differences in AngII‐induced hypertension.</p> </list-item> </list> </p> </abstract>