Testing a mechanism of control in human cholesterol metabolism: relation of arginine and glycine to insulin and glucagon.

Eight men were given 2 casein meals, one with and one without a supplement of arginine and glycine, to measure the effect on plasma amino acids, insulin and glucagon. Supplementation resulted in increased levels of plasma glucagon, glycine and arginine, a tendency to decreased insulin and significantly lower insulin/glucagon ratio, tryptophan and tyrosine. The data suggest that insulin and glucagon, which control cholesterol metabolism, respond to dietary and postprandial plasma amino acid levels of arginine and glycine.