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5-hydroxytryptamine
5-hydroxytryptamine 5-hydroxytryptamine, or serotonin, is a chemical signaling substance made from the essential amino acid tryptophan.
5-hydroxytryptamine, or serotonin, is a chemical signaling substance made from the essential amino acid tryptophan. In people it is concentrated mainly in the brain and other parts of the central nervous system, the digestive tract, and platelets, where it helps regulate nerve signaling, movement of the gut, blood clotting, and the stability of the cardiovascular system.