Influences of angiotensin on renal function in renal vascular hypertension. The scope and the magnitude of the roles which angiotensin plays in the generation and maintenance of elevated blood pressure in models of renal vascular hypertension are continuing to expand. It is now clear that specific angiotensin dependent mechanisms contribute importantly to the pathophysiology of hypertension and altered renal function in models of two-kidney, one clip hypertension in rats. The generation of angiotensin in the local intrarenal environment of the kidney is a new and potentially important mechanism contributing to altered renal function in these models. Application of antagonists of the renin-angiotensin system to rat models of renal vascular hypertension indicate that the effects of angiotensin attenuate renal hemodynamic and excretory behavior, particularly in the nonclipped kidney. Further, angiotensin may attenuate the efficiency of autoregulation of renal hemodynamics in the nonclipped kidney. Evidence that inhibition of angiotensin reverses or improves these altered hemodynamic and excretory functions indicate that angiotensin may contribute importantly to the pathophysiology of hypertension in these models by altering or impairing the ability of the nonclipped or normal kidney to excrete sodium and volume. 