serotonin

1. (biochemistry) An indoleamine neurotransmitter, 5-hydroxytryptamine, that is involved in depression, appetite, etc., and is crucial in maintaining a sense of well-being, security, etc.Examples: "Notably, mouse lines targeting genes codifying for serotonin receptors, for enzymes involved in 5-HT synthesis as Tph1 and Tph2, in its metabolism as monoaminoxidase A (MAOA) or in its re-uptake as serotonin transporter (SERT), have been generated."; "The class of antidepressants most commonly associated with sexual dysfunction is selective serotonin reuptake inhibitors, or SSRIs, which treat depression by ultimately increasing levels of the neurotransmitter serotonin in the brain."Synonyms: 5-hydroxytryptaminecountableuncountable