RT Book, Section A1 Sibley, David R. A1 Hazelwood, Lisa A. A1 Amara, Susan G. A2 Brunton, Laurence L. A2 Hilal-Dandan, Randa A2 Knollmann, Björn C. SR Print(0) ID 1162535003 T1 5-Hydroxytryptamine (Serotonin) and Dopamine T2 Goodman & Gilman's: The Pharmacological Basis of Therapeutics, 13e YR 2017 FD 2017 PB McGraw-Hill Education PP New York, NY SN 9781259584732 LK accessmedicine.mhmedical.com/content.aspx?aid=1162535003 RD 2024/03/29 AB 5-Hydroxytryptamine (5HT, serotonin) and DA are neurotransmitters in the CNS and also have prominent peripheral actions. 5HT is found in high concentrations in enterochromaffin cells throughout the GI tract, in storage granules in platelets, and throughout the CNS. The highest concentrations of DA are found in the brain; DA stores are also present peripherally in the adrenal medulla, in the plexuses of the GI, and in the enteric nervous system. Fourteen 5HT receptor subtypes and five DA receptor subtypes have been delineated by structural and pharmacological analyses. The identification of individual receptor subtypes has allowed for the development of subtype-selective drugs and the elucidation of actions of these neurotransmitters at a molecular level. Increasingly, therapeutic goals are being achieved by using drugs that selectively target one or more of the subtypes of 5HT or DA receptors, or that act on a combination of both 5HT and DA receptors.