Effects of Arginine Supplementation on Amino Acid Profiles in Blood and Tissues in Fed and Overnight Fasted Rats
Abstract
We evaluated the effect of chronic intake of arginine on amino acid concentrations in blood plasma, liver, kidneys, and soleus and extensor digitorum longus muscles. Rats were fed a standard diet or a high-arginine diet (HAD) for two months.
Half of the animals in each group were sacrificed in the fed state, and the other half after overnight fast. HAD increased blood plasma concentrations of urea, creatinine, arginine, and ornithine and decreased most of other amino acids.
Arginine and ornithine increased also in muscles and kidneys. In most of examined tissues decreased methionine, phenylalanine, threonine, asparagine, glycine, serine, and taurine.
An increase of lysine was observed in both muscle types. After overnight fast the most of the effects of HAD disappeared.
It is concluded that enhanced dietary arginine intake alters distribution of almost all amino acids, and that to get a clear picture about the effects of various nutritional interventions some biochemical measurements should be performed both in postprandial and postabsorptive states.