Brain serotonin content: physiological regulation by plasma neutral amino acids.

  title={Brain serotonin content: physiological regulation by plasma neutral amino acids.},
  author={John D. Fernstrom and Richard J. Wurtman},
  volume={178 4059},
When plasma tryptophan is elevated by the injection of tryptophan or insulin, or by the consumption of carbohydrates, brain tryptophan and serotonin also rise; however, when even larger elevations of plasma tryptophan are produced by the ingestion of protein-containing diets, brain tryptophan and serotonin do not change. The main determinant of brain tryptophan and serotonin concentrations does not appear to be plasma tryptophan alone, but the ratio of this amino acid to other plasma neutral… 

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Dietary effects on brain serotonin synthesis: relationship to appetite regulation.
  • J. Fernstrom
  • Biology, Chemistry
    The American journal of clinical nutrition
  • 1985
Evidence that the synthesis of serotonin in the brain depends directly on the amount of tryptophan available to it from the circulation is summarized and data are reviewed that attempt to show that appetite for protein and/or carbohydrates is dependent on the relationship between food intake, plasma amino acid pattern, brain tryptophile uptake, and serotonin synthesis.
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The diabetic rat's inability to experience normal carbohydrate-induced increments in brain serotonin suggests that brain functions, normally dependent on such neurochemical signals, may be abnormal.
Recent Research on the Behavioral Effects of Tryptophan and Carbohydrate
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