REDUCTION OF HYPERCHOLESTEROLEMIA AND PROTEINURIA IN NEPHRITIC RATS BY LOW-MEAT-PROTEIN DIETS

The effects of low-meat-protein diets on hypercholesterolemia and prot einuria were studied in rats with nephrotoxic serum nephritis. After a n injection of nephrotoxic serum, rats were given either a 20% meat-pr otein diet (20M), an 8.5%-meat-protein diet (8.5M), or a valine-(0.05% )-supplemented 8.5%-meat-protein diet (8.5MV) for 12 days. Urinary pro tein excreted from the 20M-fed, nephritic control rats increased rapid ly and linearly during the initial 3 days, and thereafter the high exc retion rate was maintained for up to 12 days. Two low-meat-protein die ts (8.5M, 8.5MV) commenced to suppress proteinuria 3 days after feedin g and the suppression was preserved during the rest of the experimenta l periods. Compared with the 20M, both low-meat-protein diets signific antly improved hypercholesterolemia induced in this nephritic model. T hese two diets significantly enhanced the fecal excretion of neutral s terols. They caused neither fatty liver nor severe growth retardation. These effects of 8.5MV were identical to those of 8.5M. The results s uggest that low-meat-protein feeding, without amino acid supplementati on, improves hypercholesterolemia and proteinuria in nephritis without severe protein malnutrition. The results also suggest that the hypoch olesterolemic effect of the low-meat-protein diets may be, at least in part, attributed to increased fecal excretion of steroids.