ENALAPRIL INCREASES ANTIOXIDANT ENZYME-ACTIVITY IN RENAL CORTICAL TISSUE OF 5 6-NEPHRECTOMIZED RATS/

In rats with five-sixths nephrectomy (remnant kidney), blood pressure, glomerulosclerosis, and proteinuria are significantly reduced by admi nistration of the angiotensin-converting enzyme inhibitor enalapril, d uring 16 weeks after reduction of the nephron number. The activity of catalase in remnant-kidney cortex homogenate is not influenced by enal april treatment; the activities of superoxide dismutase and glutathion e peroxidase are significantly increased. Elevated lipid peroxidation in cortex homogenates, evaluated by malondialdehyde and 4-hydroxynonen al concentrations, is not changed by treatment. Supplementation of die tary vitamin E to enalapril treatment does not alter antioxidant enzym e activities when compared to enalapril monotherapy. These results sho w that enalapril improves the balance between reactive oxygen intermed iates and antioxidant enzymes in the remnant-kidney cortex of the rat. This finding may in part explain the protective effect of angiotensin -converting enzyme inhibitors on the progression of glomerulosclerosis .