• Source: 5-HT4 receptor

5-Hydroxytryptamine receptor 4 is a protein that in humans is encoded by the HTR4 gene.




Function


This gene is a member of the family of human serotonin receptors, which are G protein-coupled receptors that stimulate cAMP production in response to serotonin (5-hydroxytryptamine). The gene product is a glycosylated transmembrane protein that functions in both the peripheral and central nervous system to modulate the release of various neurotransmitters. Multiple transcript variants encoding proteins with distinct C-terminal sequences have been described, but the full-length nature of some transcript variants has not been determined.




Location


The receptor is located in the alimentary tract, urinary bladder, heart and adrenal gland as well as the central nervous system (CNS).
In the CNS the receptor appears in the putamen, caudate nucleus, nucleus accumbens, globus pallidus, and substantia nigra, and to a lesser extent in the neocortex, raphe, pontine nuclei, and some areas of the thalamus.
It has not been found in the cerebellum.




Isoforms


Internalization is isoform-specific.




Ligands


Several drugs that act as 5-HT4 selective agonists have recently been introduced into use in both scientific research and clinical medicine. Some drugs that act as 5-HT4 agonists are also active as 5-HT3 antagonists, such as mosapride, metoclopramide, renzapride, and zacopride, and so these compounds cannot be considered highly selective. Research in this area is ongoing. Amongst these agonists prucalopride has >150-fold higher affinity for 5-HT4 receptors than for other receptors.
SB-207,145 radiolabeled with carbon-11 is used as a radioligand for 5-HT4 in positron emission tomography pig
and human
studies.




= Agonists

=
Tropisetron – partial agonist
BIMU-8
Cisapride
CJ-033,466 – partial agonist
ML-10302
Mosapride
Prucalopride
Renzapride
RS-67506
RS-67333 – partial agonist
SL65.0155 – partial agonist
Tegaserod
Zacopride
Metoclopramide
Sulpiride
Naronapride
Usmarapride




= Antagonists

=
L-lysine
Piboserod
GR-113,808 (1-methyl-1H-indole-3-carboxylic acid, [1-[2-[(methylsulfonyl)amino]ethyl]-4-piperidinyl]methyl ester)
GR-125,487
RS-39604 (1-[4-Amino-5-chloro-2-(3,5-dimethoxyphenyl)methyloxy]-3-[1-[2-methylsulphonylamino]piperidin-4-yl]propan-1-one)
SB-203,186
SB-204,070
([Methoxy-11C]1-butylpiperidin-4-yl)methyl 4-amino-3-methoxybenzoate
Chamomile (ethanol extract)




See also


5-HT receptor
5-HT1 receptor
5-HT2 receptor
5-HT3 receptor
5-HT5 receptor
5-HT6 receptor
5-HT7 receptor




References






Further reading






External links


"5-HT4". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical Pharmacology. Archived from the original on 5 June 2016. Retrieved 25 November 2008.
Human HTR4 genome location and HTR4 gene details page in the UCSC Genome Browser.
This article incorporates text from the United States National Library of Medicine, which is in the public domain.

Kata Kunci Pencarian:

• Reseptor serotonin
• 5-HT4 receptor
• Serotonin receptor agonist
• 5-HT receptor
• 5-HT2 receptor
• 5-HT3 receptor
• Prucalopride
• 5-HT6 receptor
• 5-HT2B receptor
• 5-HT1 receptor
• Levosulpiride