An indoleamine found in plants and animals, and that with dopamine, norepinephrine, epinephrine, acetylcholine and histamine, it is one of the biogenic amine neurotransmitters or neuromodulators. They are widely dispersed through the brain, but are particularly dense in the cortex. There are at least seven different types of serotonin receptors in the brain, the majority of which are excitatory. Along with norepinephrine and acetycholine, it an important transmitter in the reticular activating system along with NE and Ach. Serotonin has been implicated in feeding, emotions, mood and anxiety disorders, sexual activity, and sleep. Most anti-depressants like Prozac are thought to have their major effect on serotonergic systems in that they block serotonin uptake. Slight changes in the chemical structure of serotonin serotonin (5-hydroxytryptamine, or 5HT)result in hallucinogens such as LSD, ecstasy, and mescaline.
See Acetycholine (AcH), Dopamine, Entorhinal cortex, Mesencephalic reticular activating system, Neurotransmitters, Norepinephrine, Obsessive-compulsive disorder (OCD), PIneal gland, Raphe nuclei
a chemical, 5-hydrozytryptamine (5-HT), present in blood platelets, the gastrointestinal tract, and certain regions of the brain. It plays an important role in blood clotting, stimulating a strong heart beat, initiating sleep, fighting depression (prescription drugs that treat depression raise the brain’s levels of serotonin) and causing migraine headaches in susceptible individuals (because of its ability to constrict blood vessels or cause them to spasm). Serotonin is synthesised from the amino acid L-tryptophan. Serotonin (and, therefore, L-tyrptophan) also serves as a precursor for the pineal hormone melatonin, which regulates the body’s clock.