Protective effect of menhaden oil on renal necrosis occurring in weanling rats fed a methyl-deficient diet

Abstract

Weanling rats fed a lipotropic-deficient diet (LDD) may develop acute renal failure with morphological features that vary from focal tubular necrosis to widespread cortical necrosis and eventually reparative changes. The type of lipid in the diet influences the development of renal necrosis. The aim of this work was to study the effect of dietary menhaden oil on the development of acute renal failure induced in weanling rats fed a methyl-deficient diet. Experiment I: 40 weanling Sprague-Dawley male rats were allotted to 4 different groups and fed as follows: group 1, LDD with hydrogenated vegetable oil and corn oil as lipids; group 2, LDD with menhaden oil as lipid; group 3 and 4, similar to groups 1 and 2 plus choline. Rats were fed ad libitum until they died; surviving animals were killed on day 21. Mortality in the 4 groups was 60, 0, 0, and 10% respectively. Rats from groups 2, 3 and 4 did not show renal damage. Rats from group 1 showed tubular or cortical necrosis in dead rats and reparative changes in those killed on the 21st day. Experiment II was similar to experiment I, except that 45 weanling Wistar male rats were used and they were killed on the 7th day. All rats from group 1 showed renal necrosis; no renal damage was found in rats from groups 2, 3 and 4. Urea and creatinine alterations corroborated the renal changes. We conclude that menhaden oil displays a protective effect for renal necrosis induced by methyl-deficient diets in weanling rats.