Renal Effects of Angiotensin Converting Enzyme Inhibitors: Nondiabetic Chronic Renal Disease

Based on studies in the rat remnant kidney model, it has been proposed that glomerular hypertension is responsible for the progressive nature of chronic renal disease. In that model, therapy with angiotensin converting enzyme (ACE) inhibitors reduced glomerular pressures. As a result, glomerular injury was reduced and the rate of progression of renal disease was slowed. Thus, alterations in hemodynamics may play an important role in glomerular injury. However, it is now evident that a variety of metabolic and other factors affect the progression of renal disease. Moreover, recent studies suggest that ACE inhibitors may also have beneficial effects that are independent of alterations in glomerular pressure. In humans, the glomerular hemodynamic response to renal disease cannot be measured, and it is not known whether or under which conditions glomerular capillary pressure might be elevated. Treatment with ACE inhibitors safely lowers blood pressure without adversely affecting renal function in most patients with nondiabetic chronic renal failure. Although proteinuria and the rate of progression of renal disease may decrease in some patients, these effects are inconsistently seen. Identification of the factors that modulate this variability in response to ACE inhibition may provide new insight into the pathogenesis and treatment of progressive renal disease in humans.