Serotonin Receptors


Serotonin (5‐hydroxytryptamine, 5‐HT) receptors are found both in the central and peripheral nervous system as well as in a number of nonneuronal tissues in the gut, gastrointestinal, pulmonary, cardiovascular systems and blood cells. There are at least 15 different receptors organised in six families of the G protein‐coupled receptor (GPCR) type and one family of the Cys‐loop ligand‐gated channel type. Although the number of 5‐HT neurons in the brain is rather limited to the raphe system, projections occur across the brain and most receptors subtypes are largely distributed throughout the central nervous system (CNS). However, 95% of the 5‐HT is produced peripherally, especially in the gut, and most 5‐HT receptors are also present peripherally. It is to be expected that drugs targeting peripheral 5‐HT receptors will represent a wave of 5‐HT‐related therapies. 5‐HT has been implicated in the aetiology of a number of diseases such as migraine, hypertension, depression, anxiety, schizophrenia, irritable bowel syndrome, eating disorders and vomiting. Many of the current treatments for such disorders interact with the 5‐HT system.

Key Concepts:

  • Serotonin (5‐hydroxytryptamine, 5‐HT) is one of the oldest neurotransmitters. 5‐HT acts through a multitude of receptors in the brain and the periphery. Serotonin receptors are targeted by many drugs on the market or in clinical development for various central and peripheral pathologies such as depression, anxiety, schizophrenia, migraine, functional bowel disorders, chemotherapy‐induced emesis, eating disorders and others.

Keywords: serotonin; 5‐HT; 5‐hydroxytryptamine; receptor families and subtypes; receptor distribution; selective ligands; preclinical and clinical aspects; GPCRs; ligand‐gated channels

Figure 1.

Graphical representation of the current classification of 5‐hydroxytryptamine (5‐HT) receptors according to transduction.



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Hoyer, Daniel(Sep 2010) Serotonin Receptors. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0000125.pub2]