Species specificity of arginine deficiency-induced hepatic steatosis

Hepatic steatosis resulting from the consumption of an arginine-deficient diet in the rat was found to occur independent of age or size. The rate of lipid biosynthesis as indicated by in vitro incorporation of 14C-acetate was significantly increased in rats fed an arginine-deficient diet when expressed per milligram liver. Supplementation of the arginine-deficient diet with 1% ribose, 1% hypoxanthine or 0.2% adenine depressed the fatty infiltration caused by arginine deficiency. Inosine, xanthine or uracil supplementation did not significantly alter the fatty infiltration, liver orotic acid biosynthesis or urinary orotic excretion induced by the arginine deficiency. Increased orotic acid excretion was also observed in the mouse, hamster and rabbit fed a diet devoid of arginine. However, consumption of the, arginine-deficient diet for 21 days did not significantly alter the liver lipid content of mice, hamsters or rabbits. Although the fatty infiltration appears to be limited to the rat, altered liver nucleotides were observed in rats, hamsters and rabbits fed an arginine-deficient diet. Similarities of arginine deficiency and orotic acid feeding in various species are discussed.