Elsevier

Life Sciences

Volume 13, Issue 5, 1 September 1973, Pages 517-524
Life Sciences

Correlation between brain tryptophan and plasma neutral amino acid levels following food consumption in rats

https://doi.org/10.1016/0024-3205(73)90044-1Get rights and content

Abstract

Brain tryptophan increases significantly within two hr of the time that rats begin to consume a diet containing carbohydrate and fat, but fails to rise if the diet also contains 18–24% protein. The effects of particular diets on brain tryptophan are not well correlated with plasma tryptophan concentrations alone, but do correlate well with the ratio of plasma tryptophan to individual neutral amino acids (leucine, isoleucine, valine, tyrosine, phenylalanine) or to their sums. (These amino acids compete with tryptophan for uptake into the brain.) Carbohydrate ingestion raises brain tryptophan by elevating plasma tryptophan and depressing the plasma levels of the competing neutral amino acids; protein consumption prevents an increase in brain tryptophan by raising the plasma concentrations of the competing amino acids more than of tryptophan.

References (10)

  • W. Lovenberg et al.
  • R. Blasberg et al.

    Arch. Biochem. Biophys.

    (1965)
  • A.T.B. Moir et al.

    J. Neurochem.

    (1968)
  • R.J. Wurtman et al.
  • J.D. Fernstrom et al.

    Science

    (1971)
There are more references available in the full text version of this article.

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    Fernstrom and Wurtman were the first to report (Fernstrom and Wurtman, 1972) that brain tissue TRP levels in the rat showed a highly significant linear correlation with the ratio serum TRP/Σ (competing LNAAs). This relationship for TRP was confirmed (Fernstrom et al., 1973, 1975) and extended to other LNAAs (TYR, PHE, valine (VAL), leucine, and isoleucine) (Fernstrom et al., 1976; Fernstrom and Faller, 1978). In those early studies, however, fasted rats were typically presented with an acute meal that affected most LNAAs simultaneously (Fernstrom et al., 1976; Fernstrom and Faller, 1978).

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