- Serotonin (also known as 5-HT) is a neurotransmitter that is found throughout the body. High concentrations are found in the CNS, blood platelets, and certain cells in the gastrointestinal tract.1
- Serotonin is synthesized from the amino acid tryptophan, and is removed from the synaptic cleft by reuptake or enzymatic breakdown.2
- There are many receptor subtypes for serotonin.1,3
- Serotonergic neurons project widely throughout the brain from their origin in the raphe nuclei of the brainstem.1
The wide dispersal of serotonergic neurons throughout the brain enables serotonin to be involved in modulating diverse body functions:1,3,5
- mood
- sleep
- cognition
- sensory processing
- pain perception
- movement
- regulation of internal temperature
- appetite
- sexual behaviour
- hormone secretion.
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