A concentrated mixture of amino acids and dipeptides for total parenteral nutrition
Vazquez, J.A.; Paleos, G.A.; Lochs, H.; Langer, K.; Brandl, M.; Adibi, S.A.
Infusionstherapie und Klinische Ernahrung 13(4): 193-198
1986
ISSN/ISBN: 0378-0791 PMID: 3093380 Document Number: 281783
The utility of a 20% mixture of amino acids and dipeptides as the nitrogen source for total parenteral nutrition (TPN) was studied with baboons. The mixture, besides containing all 8 essential amino acids and a number of non-essential amino acids (glutamate, aspartate, arginine, histidine, serine, ornithine and alanine), contained 6 dipeptides (Gly-Ile, Gly-Leu, Gly-Val, Gly-Tyr, Gly-Gln and Ala-Gln) and acetylcysteine. A week of TPN was preceded by one week of oral feeding. The energy intake and composition during the two periods was identical except for the source of N, which was intact protein during the oral period and the mixture of amino acids and dipeptides during the parenteral period. There was no significant difference between gain in body weight or N balance during the two periods. There were selective increases in plasma and muscle concentrations of amino acids during the parenteral period, which seemed to reflect the amino acid enrichment of the N source. The efficient utilization of dipeptides was evidenced by their small concentrations in plasma and urine. The urinary excretion of dipeptides was about 1% of the amount infused. This efficiency of dipeptide utilization persisted even when the infusion rate of the amino acid and dipeptide mixture was increased 7-fold. There was no change in liver, kidney or immune function during the parenteral period. The data indicate the efficacy and safety of the mixture of amino acids and dipeptides as the source of N for parenteral nutrition.