Summary
The postprandial plasma amino acid response to test meals containing different amino acid mixtures was analysed in six young adults. The amount of amino acids given in each test meal was equivalent with 3.5g of nitrogen. Each test meal also contained a large amount of carbohydrate (mainly as wheat starch). Five different amino acid mixtures were used, and the effects on the plasma amino acid response of different dietary levels of lysine, isoleucine and methionine were studied in detail. The plasma amino acid responses were evaluated both by a modified Longenecker and Hause procedure (PAA ratios) and by the procedure proposed by Graham and Placko (percentage changes in the postprandial essential amino acid molar ratios). The plasma amino acid response of lysine was found to be less sensitive to reductions in the dietary supply than the isoleucine and methionine responses evaluated by these procedures. The influence of altered levels of dietary supply on the postprandial plasma concentrations of isoleucine and methionine seemed to be specifically great at the intake levels where these essential amino acids become limiting for protein utilization according to the amino acid score of the test mixtures. The nutritional significance of the postprandial pattern and level of essential amino acids is discussed on basis of the present results. Experimental conditions and evaluation models are examined with regard to the use of single-meal plasma amino acid responses to assess the protein quality of human diets.
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Ljungqvist, B. G.: Plasma amino acid response to single test meals in humans. I. A background review. Res. Exp. Med. (Berl.)174, 1 (1978)
Björnesjö, K. B., Engsner, G., Gobezie, A., Jagenburg, R., Ljungqvist, B. Mellander, O.: Plasma amino acids in feeding children with a supplementary food mixture. Environm. Child Health19, 129 (1973)
Ljungqvist, B. G., Olsson, M. E., Svanberg, U. S.-O.: Plasma amino acid response to single test meals in humans. III. Supplementary effect of dried skim milk and methionine on a vegetable protein mixture. Res. Exp. Med. (Berl.)174, 29 (1978)
Ljungqvist, B. G., Boström, S. L., Sjöberg, L. B., Svanberg, U. S.-O.: Plasma amino acid response to single test meals in humans. IV. Four lowcost protein supplements evaluated by chemical analysis, rat bioassay and plasma amino acid response. Res. Exp. Med. (in press, 1979)
Ljungqvist, B. G., Björnesjö, K. B., Gebre-Medhin, M., Habte, D., Meeuwisse, G., Mellander, O., Svanberg, U. S.-O.: Plasma amino acid response to single test meals in humans. V. Ethiopian preschool children given low-cost protein supplements. Res. Exp. Med. (in press, 1979)
Energy and protein requirements. Report of a Joint FAO/WHO Ad Hoc Expert Committee. WHO Techn. Rep. Ser. No.522 (1973)
Benson, J. V. Jr., Patterson, J. A.: Chromatographic advances in amino acids and peptide analysis using spherical resins and their applications in biochemistry and medicine. In: New techniques in amino acid, peptide and protein analysis, Niederwieser, A., Pataki, G. (eds.), p. 1. Ann. Arbor Science Publishers Inc. 1971
Hess, S. M., Udenfriend, S.: A fluorometric procedure for the measurement of tryptamine in tissue. J. Pharmacol. Exp. Ther.127, 175 (1959)
Graham, G. G., Placko, R. P.: Postprandial plasma free methionine as an indicator of dietary methionine adequacy in the human infant. J. Nutr.103, 1347 (1973)
Longenecker, J. B., Hause, N. L.: Relationship between plasma amino acids and composition of the ingested protein. Arch. Biochem.84, 46 (1959)
Longenecker, J. B., Hause, N. L.: Relationship between plasma amino acids and composition of the ingested protein. II. A shortened procedure to determine plasma amino (PAA) ratios. Am. J. Clin. Nutr.9, 356 (1961)
Wilcoxon, F.: Individual comparisons by ranking methods. Biometrics1, 80 (1945)
Pratt, J. W.: Remarks on zeros and ties in the Wilcoxon signed rank procedures. J. Amer. Stat. Ass.54, 655 (1959)
Pitman, E. J. G.: Notes on non-parametric statistical inference. Columbia University 1948 (duplicated report)
Eeden, C. van, Benard, A.: A general class of distribution free tests for symmetry containing the tests of Wilcoxon and Fisher. II. Indag. Math.19, 392 (1957)
Hodges, J. L., Lehmann, E. L.: The efficiency of some nonparametric competitors of thet-test. Ann. Math. Statist.27, 324 (1956)
Swendseid, M. E., Watts, J. H., Harris, C. L., Tuttle, S. G.: An evaluation of the FAO amino acid reference pattern in human nutrition. I. Studies with young men. J. Nutr.75, 295 (1961)
Clark, H. E., Stuff, J. T., Moon, W. H., Bailey, L. B.: Nitrogen retention and plasma amino acids in men who consumed isonitrogenous diets containing egg albumen or mixtures of amino acids. Am. J. Clin. Nutr.28, 316 (1975)
Kirk, M. C., Metheny, M., Reynolds, M. S.: Nitrogen balance of young women fed amino acids in the FAO reference pattern, the milk pattern and the peanut pattern. J. Nutr.77, 448 (1962)
Clark, H. E., Moon, W. H., Bailey, L. B., Panemangelore, M.: Nitrogen retention and plasma amino acids of adults who consumed isonitrogenous diets containing rice and milk or wheat versus their constituent amino acids. Am. J. Clin. Nutr.29, 1343 (1976)
Pion, R., Prugnaud, J., Rerat, A.: Kinetics of the absorption of herring meal amino acids and of DL-methionine by the pig. Nutr. Rep. Int.6, 331 (1972)
Rolls, B. A., Porter, J. W. G., Westgarth, D. R.: The course of digestion of different food proteins in the rat. III. The absorption of proteins given alone and with supplements of their limiting amino acids. Brit. J. Nutr.28, 283 (1972)
Cooke, A. R., Moulang, I.: Control of gastric emptying by amino acids. Gastroenterology62, 528 (1972)
Orok, E. J., Bowland, J. P.: Rapeseed, peanut and soybean meals as protein supplements: dietary amino acid composition and postprandial plasma amino acid pattern as indices of performance of pigs. Can. J. Anim. Sc.55, 337 (1975)
Smith, R. E.: Importance of an accurate reference diet in the evaluation of proteins for chick growth using plasma amino acid titers. J. Nutr.89, 271 (1966)
Young, V. R.: The role of the skeletal and cardiac muscles in the regulation of protein metabolism. In: Mammalian protein metabolism, Munro, H. N. (ed.), Vol. 4, p. 585. New York: Academic Press 1970
Munro, H. N.: Free amino acid pools and their role in regulation. In: Mammalian protein metabolism, Munro, H. N. (ed.), Vol. 4, p. 299. New York: Academic Press 1970
Bergström, J., Fürst, P., Norée, L. O., Vinnars, E.: Intracellular free amino acid concentration in human muscle tissue. J. Appl. Physiol.36, 693 (1974)
Pion, R.: The relationships between the levels of free amino acids in blood and muscle and the nutritive value of proteins. In: Proteins in human nutrition, Porter, J. W. G., Rolls, B. A. (eds.), p. 329. New York: Academic Press 1973
Ljungqvist, B. G., Blomstrand, E., Hellström, Å., Lindell, I., Olsson, M. E., Svanberg, U. S.-O.: Plasma amino acid response to single test meals in humans. VI. Determination of available lysine. Res. Exp. Med. (in press, 1979)
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This study was supported by grants from the Swedish Medical Research Council (grant no. K75-03X-3139-04A and no. B76-03X-3139-05B) and from the Swedish Nutrition Foundation
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Ljungqvist, B.G., Svanberg, U.S.O. & Young, V.R. Plasma amino acid response to single test meals in humans. Res. Exp. Med. 174, 13–28 (1978). https://doi.org/10.1007/BF01851935
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DOI: https://doi.org/10.1007/BF01851935