Plasma Renin and Vascula Complications in Substrains of the Spontaneously Hypertensive Rat, with a Reference to Water and Electrolyte Balance

Abstract

The stroke-prone and stroke-resistant substrains of the spontaneously hypertensive rat (SHR) were employed for an evaluation of possible role of renin-angiotensin system and of water and electrolyte balances in inducing hypertensive vascular lesion. Serial study on plasma renin level and vascular changes did not support the hypothesis that plasma renin is a major risk factor in the development of cardiovascular complications. The high plasma renin level seen in advanced stages of hypertension appeared to be a result of severe vascular damages, indicating malignant transformation of hypertension. In this state, water turnover was enhanced without any abnormality in electrolyte balance. A possible mechanism involved in the malignant course of hypertension is discussed.