5-HT receptors, 5-hydroxytryptamine receptors, or serotonin receptors, are a group of G protein-coupled receptor and ligand-gated ion channels found in the central and peripheral nervous systems. They mediate both excitatory and inhibitory neurotransmission. The serotonin receptors are activated by the neurotransmitter serotonin, which acts as their natural ligand.
The 5-HT2A receptor is a subtype of the 5-HT2 receptor that belongs to the serotonin receptor family and is a G protein-coupled receptor (GPCR). The 5-HT2A receptor is a cell surface receptor, but has several intracellular locations.
meta-Chlorophenylpiperazine (mCPP) is a psychoactive drug of the phenylpiperazine class. It was initially developed in the late-1970s and used in scientific research before being sold as a designer drug in the mid-2000s. It has been detected in pills touted as legal alternatives to illicit stimulants in New Zealand and pills sold as "ecstasy" in Europe and the United States.
The 5-HT2C receptor is a subtype of the 5-HT2 receptor that binds the endogenous neurotransmitter serotonin (5-hydroxytryptamine, 5-HT). Like all 5-HT2 receptors, it is a G protein-coupled receptor (GPCR) that is coupled to Gq/G11 and mediates excitatory neurotransmission. HTR2C denotes the human gene encoding for the receptor, that in humans is located on the X chromosome. As males have one copy of the gene and females have one of the two copies of the gene repressed, polymorphisms at this receptor can affect the two sexes to differing extent.
5-Hydroxytryptamine (serotonin) receptor 5A, also known as HTR5A, is a protein that in humans is encoded by the HTR5A gene. Agonists and antagonists for 5-HT receptors, as well as serotonin uptake inhibitors, present promnesic (memory-promoting) and/or anti-amnesic effects under different conditions, and 5-HT receptors are also associated with neural changes.
Quipazine is a serotonergic drug of the piperazine group which is used in scientific research. It was originally intended as an antidepressant but never developed for medical use.
Ro60-0175 is a drug developed by Hoffmann–La Roche, which has applications in scientific research. It acts as a potent and selective agonist for both the 5-HT2B and 5-HT2C serotonin receptor subtypes, with good selectivity over the closely related 5-HT2A subtype, and little or no affinity at other receptors.
TFMFly is a compound related to psychedelic phenethylamines such as 2C-B-FLY and 2C-TFM. It was first reported in 2005 by a team at Purdue University led by David Nichols. It acts as a potent agonist at the 5HT2A serotonin receptor subtype, and is a chiral compound with the more active (R) enantiomer having a Ki of 0.12 nM at the human 5-HT2A receptor. While the fully aromatic benzodifurans such as Bromo-DragonFLY generally have higher binding affinity than saturated compounds like 2C-B-FLY, the saturated compounds have higher efficacy as agonists.
CGS-12066A is a drug which acts as a potent and selective agonist for the 5-HT1B receptor with lower affinity for the three 5-HT2 receptor subtypes. It is used for studying the role of the 5-HT1B receptor in various processes including perception of pain and the sleep-wake cycle.
Osemozotan (MKC-242) is a selective 5-HT1A receptor agonist with some functional selectivity, acting as a full agonist at presynaptic and a partial agonist at postsynaptic 5-HT1A receptors. 5-HT1A receptor stimulation influences the release of various neurotransmitters including serotonin, dopamine, norepinephrine, and acetylcholine. 5-HT1A receptors are inhibitory G protein-coupled receptor.
RH-34 is a compound which acts as a potent and selective partial agonist for the 5-HT2A serotonin receptor subtype. It was derived by structural modification of the selective 5-HT2A antagonist ketanserin, with the 4-(p-fluorobenzoyl)piperidine moiety replaced by the N-(2-methoxybenzyl) pharmacophore found in such potent 5-HT2A agonists as NBOMe-2C-B and NBOMe-2C-I. This alteration was found to retain 5-HT2A affinity and selectivity, but reversed activity from an antagonist to a moderate efficacy partial agonist.
1-(1-Naphthyl)piperazine (1-NP) is a drug which is a phenylpiperazine derivative. It acts as a non-selective, mixed serotonergic agent, exerting partial agonism at the 5-HT1A, 5-HT1B, 5-HT1D, 5-HT1E, and 5-HT1F receptors, while antagonizing the 5-HT2A, 5-HT2B, and 5-HT2C receptors. It has also been shown to possess high affinity for the 5-HT3, 5-HT5A, 5-HT6, and 5-HT7 receptors, and may bind to 5-HT4 and the SERT as well. In animals it produces effects including hyperphagia, hyperactivity, and anxiolysis, of which are all likely mediated predominantly or fully by blockade of the 5-HT2C receptor.
VER-3323 is a drug which acts as a selective agonist for both the 5-HT2B and 5-HT2C serotonin receptor subtypes, with moderate selectivity for 5-HT2C, but relatively low affinity for 5-HT2A. It has potent anorectic effects in animal studies.
Indorenate (TR-3369), is a tryptamine derivative which acts as an agonist at the 5-HT1A, 5-HT1B and 5-HT2C serotonin receptors. It has anxiolytic, antihypertensive and anorectic effects, predominantly through action at 5-HT1A, but with some contribution from the 5-HT1B and 5-HT2C subtypes, and possibly some other non-serotonergic targets also.
SB-206553 is a drug which acts as a mixed antagonist for the 5-HT2B and 5-HT2C serotonin receptors. It has anxiolytic properties in animal studies and interacts with a range of other drugs. It has also been shown to act as a positive allosteric modulator of α7 nicotinic acetylcholine receptors. Modified derivatives of SB-206553 have been used to probe the structure of the 5-HT2B receptor.
S32212 is a drug which is under preclinical investigation as a potential antidepressant medicine. It behaves as a selective, combined 5-HT2C receptor inverse agonist and α2-adrenergic receptor antagonist (at all three subtypes—α2A, α2B, and α2C) with additional 5-HT2A and, to a lesser extent, 5-HT2B receptor antagonistic properties, and lacks any apparent affinity for the monoamine reuptake transporters or for the α1-adrenergic, H1, or mACh receptors. This profile of activity is compatible with the definition of a noradrenergic and specific serotonergic antidepressant (NaSSA), and as such, S32212 could in turn be classified as a NaSSA.
5-HT2C receptor agonists are a class of drugs that activate 5-HT2C receptors. They have been investigated for the treatment of a number of conditions including obesity, psychiatric disorders, sexual dysfunction and urinary incontinence.
PHA-57378 is a drug which acts as an agonist at serotonin 5-HT2 receptors, having a binding affinity of 4.1 nM at the 5-HT2A subtype and 4.3 nM at 5-HT2C. It has anxiolytic effects in animal studies.
25I-NB34MD (NB34MD-2C-I) is a derivative of the phenethylamine hallucinogen 2C-I, which acts as a potent partial agonist for the human 5-HT2A receptor, and presumably has similar properties to 2C-I. It has a binding affinity of 0.67nM at the human 5-HT2A receptor, making it several times weaker than its positional isomer 25I-NBMD and a similar potency to 25I-NBF.
WAY-163,909 is a drug which acts as a potent and reasonably selective agonist for the serotonin 5-HT2C receptor. It has antipsychotic-like effects in animal models, and has been used to study the role of the 5-HT2C receptor subtype in the action of addictive drugs such as nicotine and methamphetamine.
