Tryptophan Metabolism in Healthy Subjects: Influence of Pyridoxine after Single or Repeated Administrations
Common wisdom presently suggests that the neurobiological basis for therapies of sleep disorders with oral loading doses of L-tryptophan (TRP) is the increase in synthesis, storage and/or release of serotonin (5-HT) in syn-aptosomal compartments from TRP transported from plasma to central neurons. Quantitatively, the conversion of TRP to 5-HT and/or biologically active in-dole derivatives in brain structures is very small compared to tryptophan oxidation in the periphery through both dioxygenases (indole 2, 3-dioxygenase in lung, intestine and other organs and liver tryptophan 2, 3-dioxygenase). Therefore, the elucidation of strategies leading to an increased transport of the administered TRP dose into the brain and thus utilization within neurons is of considerable importance.
KeywordsSleep Disorder Tryptophan Metabolism Large Neutral Amino Acid Neurobiological Basis Common Wisdom
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