The Renin Angiotensin System, the Kidney, and the Pathogenesis of Hypertension

Summary

Some individuals enjoy a high salt diet with impunity: others, on the other hand, raise their blood pressure and suffer the consequences. Multiple observations suggest that familial, probably genetic, factors are involved and that the abnormality resides in the kidney. We have identified a group of patients, called “non-modulators,” in whom impaired responsiveness of the kidney and adrenal to Angiotension H (All) with shifts in salt intake, is associated with failure of renal blood flow to change as salt intake changes, impaired ability to handle a salt load, and sodium-sensitive hypertension. The abnormality is familial and probably inherited. Angiotensin converting enzyme (ACE) inhibition corrects many of the associated abnormalities, increases renal blood flow, and enhances the ability of the kidney to handle a salt load — an important contribution, we believe, to the antihypertensive effect. The renal abnormality may also predispose to progressive renal injury if an additional abnormality, such as diabetes mellitus, is superimposed.