[Interrelationship between the brain and kidney renin--angiotensin systems in combined hypertension: the effect of a central block with saralasin].

Conditions for Simultaneous stimulation of cerebral and renal renin-angiotension systems (RAS) are created in the examined by us model of combined cerebral and renal ischemic hypertension. As a results of interaction between them the effect o cerebral RAS predominates, since renin concentration in the medulla oblongata is elevated while the renal renin concentration remains unchanged, but the plasma renin activity is lowered. The blocking of the action of cerebral angiotension by the venously administered angiotensin antagonist saralasin does not alter substantially blood pressure, but causes elevation of the renal renin concentration in the ischemic and intact kidney and normalization of plasma renin activity, without affecting the level of sodium and potassium.