QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Hagemeister, H. Articles by Barth, C. A. Search for Related Content PubMed PubMed Citation Articles by Hagemeister, H. Articles by Barth, C. A.

Plasma Amino Acids and Cholesterol Following Consumption of Dietary Casein or Soy Protein in Minipigs^{1, 2,}

Institut für Physiologie und Biochemie der Ernährung ^* Institut für Milcherzeugung, Bundesanstalt für Milchforschung, D-2300 Kiel, Federal Republic of Germany

Numerous investigators have claimed that protein-induced differences in plasma cholesterol are mediated by differences in amino acid composition. We have explored whether the venous postprandial amino acid profile reflects differences in the amino acid composition of the protein consumed. Six adult Göttingen miniature pigs were fed a semisynthetic diet based on either casein or soy protein isolate. Frequent blood sampling was performed over a whole day after consumption of each diet for 6 wk. Postprandial plasma amino acid concentrations reached their maxima within the first 3 h. A group of eight protein amino acids (Met, Arg, Tyr, Val, Trp, Leu, Lys and Cys) exhibited the most marked and significant protein-dependent differences during this early postprandial phase, whereas Thr and His showed less marked differences. With one exception (Ser) all protein amino acids exhibited venous plasma concentration changes in qualitative accordance with their content in the dietary protein consumed. In quantitative terms, however, venous plasma amino acid changes were less marked than expected from the amino acid composition of the dietary proteins. We conclude that neither the considerable number of amino acids showing differences as reported herein nor the multitude of contradictory reports by others concerning single amino acids affecting serum cholesterol favor the hypothesis that one or several amino acid(s) cause protein-induced hypercholesterolemia.

KEY WORDS: • plasma amino acids • postprandial changes • minipig • casein • soy

¹ Part of this work was presented at the 43rd Annual Meeting of the Gesellschaft für Ernährungsphysiologie, Göttingen, FRG, 1989.

² We acknowledge the financial support of the European Commission, project VO (EWG) No. 282/84-26-1 "Eiweißbewertung II."

Manuscript received 30 October 1989. Revision accepted 22 May 1990.