Abstract
1. The reciprocal interference between l-leucine, l-isoleucine and l-valine during absorption was studied in rats both in vivo and with an everted-sac preparation in vitro. 2. After feeding with the amino acids alone there was a considerable increase in their concentration in the intestinal lumen followed by a rapid disappearance, indicating efficient absorption. Absorption was reflected by a high concentration of the respective amino acids in the portal plasma. Isoleucine and valine inhibited the absorption of leucine, and leucine inhibited the absorption of isoleucine and valine. Inhibition of absorption by the interfering amino acid was generally partly overcome after 30–60min., probably through the absorption of the interfering amino acid. At that time the rise in the concentration of the amino acid in portal plasma began. 3. These results were confirmed by experiments in vitro: isoleucine and valine inhibited the absorption rate of leucine, and leucine that of isoleucine and valine. 4. Active absorption of amino acids was rapid at low concentrations and depressed at higher concentrations.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- BENTON D. A., HARPER A. E., SPIVEY H. E., ELVEHJEM C. A. Leucine, isoleucine and valine relationships in the rat. Arch Biochem Biophys. 1956 Jan;60(1):147–155. doi: 10.1016/0003-9861(56)90406-4. [DOI] [PubMed] [Google Scholar]
- DAWSON R., PORTER J. W. An investigation into protein digestion with 14C-labelled protein. 2. The transport of 14C-labelled nitrogenous compounds in the rat and cat. Br J Nutr. 1962;16:27–38. doi: 10.1079/bjn19620003. [DOI] [PubMed] [Google Scholar]
- GOLDBERG A., GUGGENHEIM K. The digestive release of amino acids and their concentrations in the portal plasma of rats after protein feeding. Biochem J. 1962 Apr;83:129–135. doi: 10.1042/bj0830129. [DOI] [PMC free article] [PubMed] [Google Scholar]
- HARPER A. E., MONSON W. J., ARATA D. A., BENTON D. A., ELVEHJEM C. A. Influence of various carbohydrates on the utilization of low protein rations by the white rat. II. Comparison of several proteins and carbohydrates; growth and liver fat. J Nutr. 1953 Dec 10;51(4):523–537. doi: 10.1093/jn/51.4.523. [DOI] [PubMed] [Google Scholar]
- KAMIN H., HANDLER P. Effect of presence of other amino acids upon intestinal absorption of single amino acids in the rat. Am J Physiol. 1952 May;169(2):305–308. doi: 10.1152/ajplegacy.1952.169.2.305. [DOI] [PubMed] [Google Scholar]
- REISER S., CHRISTIANSEN P. A. INTESTINAL TRANSPORT OF AMINO ACIDS STUDIED WITH L-VALINE. Am J Physiol. 1965 May;208:914–921. doi: 10.1152/ajplegacy.1965.208.5.914. [DOI] [PubMed] [Google Scholar]
- ROGERS Q. R., SPOLTER P. D., HARPER A. E. Effect of leucineisoleucine antagonism on plasma amino acid pattern of rats. Arch Biochem Biophys. 1962 Jun;97:497–504. doi: 10.1016/0003-9861(62)90113-3. [DOI] [PubMed] [Google Scholar]
- SPOLTER P. D., HARPER A. E. Effect of leucine-isoleucine and valine antagonism and comparison with the effect of ethionine on rat liver regeneration. Arch Biochem Biophys. 1963 Mar;100:369–377. doi: 10.1016/0003-9861(63)90100-0. [DOI] [PubMed] [Google Scholar]