5-Hydroxytryptamine, 5-HT, 3-(2-Aminoethyl)indole-5-ol, C14H21N2O, M=176,22 g/mol
Serotonin is a monoamine neurotransmitter, responsible both in the central nervous system (depressions, migraine, fear conditions, receptor: 5-HT2) as well as the blood circulation system (blood pressure, aggregation of the blood panels, receptor: 5-HT1) and in the gastrointestinal tract (appetite).
The biogenesis arrives from the amino acid L-Tryptophan by means of Tryptophanhydroxylase, the dismantling by the enzyme Monoaminooxidase (MAO). Increased Serotonine levels leads to a feeling of the well-being, therefore the designation "luck hormone". Since Serotonine does not penetrate the blood-brain barrier, there could be only an indirect influence either by MAO-Inhibitors, e.g. Moclobemid, or by reuptake Inhibitors (selective Serotonin receptor inhibitors, SSRI), e.g. Fluoxetine, Paroxetine, Sertraline and Citalopram. These antidepressants have replaced the extensivly usage of tricylic and tetracyclic antidepressants in former times for the treatment of depressions and fear disturbances, since they work more strongly and above all more specifically and show smaller adverse effects.
LSD strengthens the effect of Serotonin (Agonist), Cocain restrains its effect (antagonist).
Serotonin was first discovered in 1948 by M. Rapport as a vasoconstrictor substance in blood serum, therefore the name serotonin reflects to a serum agent, affecting the vascular tone. Rapport also identified the chemical structure as 5-Hydroxytrptamine.