Serotonin

n. essential hormone and neurotransmitter derived from the amino acid tryptophan, precursor of the hormone melatonin (Physiology)

For the professional wrestling stable, see Raven's Nest. Serotonin (pronounced ) (5-hydroxytryptamine, or 5-HT) is a monoamine neurotransmitter synthesized in serotonergic neurons in the central nervous system (CNS) and enterochromaffin cells in the gastrointestinal tract of animals including humans. Serotonin is also found in many mushrooms and plants, including fruits and vegetables.
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Noun
1. a neurotransmitter involved in e.g. sleep and depression and memory
(synonym) 5-hydroxytryptamine
(hypernym) monoamine neurotransmitter

A chemical in the brain involved in the transmission of nerve impulses. Serotonin.can trigger the release of substances in the blood vessels of the brain that in turn cause the pain of the migraine.

A hormone found in the brain, platelets, digestive tract, and pineal gland. It acts both as a neurotransmitter (a substance that nerves use to send messages to one another) and a vasoconstrictor (a substance that causes blood vessels to narrow). A lack of serotonin in the brain is thought to be a cause of depression. Also called 5-hydroxytryptamine.