Aldosterone acts on the kidney, not the brain, to cause mineralocorticoid hypertension in sheep

Abstract

Objective: To determine the extent to which mineralocortioid hypertension depends on a direct action of aldosterone on the kidney or on the brain. Methods: Studies were performed in conscious sheep that were previously uninephrectomized, implanted with silastic cannulae in the renal artery of the remaining kidney, and had guide tubes implanted over the lateral cerebral ventricles. The effect of aldosterone, infused either intrarenally (i.r.; 2 μg/h) or intravenously (i.v.; 2 and 10 μg/h) for 10 days (n = 5), on arterial pressure and fluid and electrolyte balance was determined. The i.r. (2 μg/h) and i.v. (10 μg/h) doses were calculated to give similar intrarenal concentrations of aldosterone..