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. 1982 Aug;23(8):670–674. doi: 10.1136/gut.23.8.670

Comparison of plasma and intraluminal amino acid profiles in man after meals containing a protein hydrolysate and equivalent amino acid mixture.

J E Hegarty, P D Fairclough, K J Moriarty, M L Clark, M J Kelly, A M Dawson
PMCID: PMC1419135  PMID: 7095563

Abstract

Plasma and intraluminal amino acid profiles were compared in normal subjects 30, 60, 120, 180 minutes after meals containing either a peptide-rich protein hydrolysate (H) or an equivalent free amino acid mixture (AA) as the nitrogen source. Except for asparagine (30 minutes) and glutamine (30 and 60 minutes), which were absorbed to a significantly (p less than 0.05) greater extent from the peptide mixture, there were no significant differences in the plasma increments of the remaining 13 amino acids at any time interval after the meals. Positive correlations (p less than 0.01 or less) between the amino acid composition of the hydrolysate and amino acid meals and both (1) the post-prandial increments in the individual plasma amino acids and (2) the residual intraluminal amino acid content suggested that the amino acid composition of ingested protein, rather than specialised free amino acid and peptide transport systems, dictated the pattern of amino acid absorption. The studies provide no evidence that peptides rather than free amino acids are the ideal nitrogen source in elemental diets.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Adibi S. A., Mercer D. W. Protein digestion in human intestine as reflected in luminal, mucosal, and plasma amino acid concentrations after meals. J Clin Invest. 1973 Jul;52(7):1586–1594. doi: 10.1172/JCI107335. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. DENTON A. E., ELVEHJEM C. A. Availability of amino acids in vivo. J Biol Chem. 1954 Jan;206(1):449–454. [PubMed] [Google Scholar]
  3. Dent C. E. Studies on the absorption of proteins: the amino-acid pattern in the portal blood. Biochem J. 1949;44(3):318–335. [PMC free article] [PubMed] [Google Scholar]
  4. FRAME E. G. The levels of individual free amino acids in the plasma of normal man at various intervals after a high-protein meal. J Clin Invest. 1958 Dec;37(12):1710–1723. doi: 10.1172/JCI103763. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Fairclough P. D., Hegarty J. E., Silk D. B., Clark M. L. Comparison of the absorption of two protein hydrolysates and their effects on water and electrolyte movements in the human jejunum. Gut. 1980 Oct;21(10):829–834. doi: 10.1136/gut.21.10.829. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Gray G. M., Cooper H. L. Protein digestion and absorption. Gastroenterology. 1971 Oct;61(4):535–544. [PubMed] [Google Scholar]
  7. Hegarty J. E., Fairclough P. D., Moriarty K. J., Kelly M. J., Clark M. L. Effects of concentration on in vivo absorption of a peptide containing protein hydrolysate. Gut. 1982 Apr;23(4):304–309. doi: 10.1136/gut.23.4.304. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Marrs T. C., Addison J. M., Burston D., Matthews D. M. Changes in plasma amino acid concentrations in man after ingestion of an amino acid mixture simulating casein, and a tryptic hydrolysate of casein. Br J Nutr. 1975 Sep;34(2):259–265. doi: 10.1017/s000711457500030x. [DOI] [PubMed] [Google Scholar]
  9. Matthews D. M. Intestinal absorption of peptides. Physiol Rev. 1975 Oct;55(4):537–608. doi: 10.1152/physrev.1975.55.4.537. [DOI] [PubMed] [Google Scholar]
  10. Nasset E. S., Ju J. S. Amino acids and glucose in human blood plasma after beef and nonprotein meals. Proc Soc Exp Biol Med. 1969 Dec;132(3):1077–1080. doi: 10.3181/00379727-132-34370. [DOI] [PubMed] [Google Scholar]
  11. RICHMOND J., GIRDWOOD R. H. Observations on aminoacid absorption. Clin Sci. 1962 Jun;22:301–314. [PubMed] [Google Scholar]
  12. Silk D. B., Chung Y. C., Berger K. L., Conley K., Beigler M., Sleisenger M. H., Spiller G. A., Kim Y. S. Comparison of oral feeding of peptide and amino acid meals to normal human subjects. Gut. 1979 Apr;20(4):291–299. doi: 10.1136/gut.20.4.291. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Silk D. B., Clark M. L., Marrs T. C., Addison J. M., Burston D., Matthews D. M., Clegg K. M. Jejunal absorption of an amino acid mixture simulating casein and an enzymic hydrolysate of casein prepared for oral administration to normal adults. Br J Nutr. 1975 Jan;33(1):95–100. doi: 10.1079/bjn19750012. [DOI] [PubMed] [Google Scholar]
  14. Yearick E. S., Nadeau R. G. Serum amino acid response to isocaloric test meals. Am J Clin Nutr. 1967 Apr;20(4):338–344. doi: 10.1093/ajcn/20.4.338. [DOI] [PubMed] [Google Scholar]
  15. Young E. A., Heuler N., Russell P., Weser E. Comparative nutritional analysis of chemically defined diets. Gastroenterology. 1975 Dec;69(6):1338–1345. [PubMed] [Google Scholar]

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