Synthesis of Serotonin by a Second Tryptophan Hydroxylase Isoform

The neurotransmitter serotonin [5-hydroxytryptamine (5-HT)] is causally involved in multiple central nervous facets of mood control and in regulating sleep, anxiety, alcoholism, drug abuse, food intake, and sexual behavior ([1][1]). In peripheral tissues, 5-HT regulates vascular tone, gut motility,