Induction of renal growth and injury in the intact rat kidney by dietary deficiency ofantioxidants

We report induction of renal growth and injury in the intact rat kidney using a diet deficient in vitamin E and selenium. This diet was imposed in 3-wk-old male weanling rats, and after 9 wk, enhancement of growth, characterized by increased wet weight, dry weight, protein content, and DNA content ap-peared. Morphometric analyses revealed increased kidney vol-ume, tubular epithelial volume, and mean glomerular volume. There were no differences in nephron number. The animals on the deficient diet displayed increased urinary protein excretion at 9 wk. Renal injury was also characterized by an interstitial cellular infiltrate and diminutions in glomerular filtration rate. Enhanced growth and injury were antedated by increased renal ammoniagenesis. The deficient diet did not induce metabolic acidosis, potassium depletion, glucose intolerance, or elevated plasma amino acid concentration. Enhancement of renal growth and ammoniagenesis by the deficient diet was not sup-pressible by chronic alkali therapy. Stimulation of renal growth could not be ascribed to increased intrarenal iron, in-duction of ornithine decarboxylase, or alterations in glomeru-lar hemodynamics. Stimulation of renal ammoniagenesis by dietary deficiency of antioxidants is a novel finding, as is in-duction of growth and injury. We suggest that increased renal ammoniagenesis contributes to induction of renal growth an