PB-28 is an agonist of the sigma-2 receptor.
The human muscarinic acetylcholine receptor M5, encoded by the CHRM5 gene, is a member of the G protein-coupled receptor superfamily of integral membrane proteins. It is coupled to Gq protein. Binding of the endogenous ligand acetylcholine to the M5 receptor triggers a number of cellular responses such as adenylate cyclase inhibition, phosphoinositide degradation, and potassium channel modulation. Muscarinic receptors mediate many of the effects of acetylcholine in the central and peripheral nervous system. The clinical implications of this receptor have not been fully explored; however, stimulation of this receptor is known to effectively decrease cyclic AMP levels and downregulate the activity of protein kinase A (PKA).
The muscarinic acetylcholine receptor M2, also known as the cholinergic receptor, muscarinic 2, is a muscarinic acetylcholine receptor that in humans is encoded by the CHRM2 gene. Multiple alternatively spliced transcript variants have been described for this gene.
Dopamine receptor D3 is a protein that in humans is encoded by the DRD3 gene.
Metabotropic glutamate receptor 2 (mGluR2) is a protein that, in humans, is encoded by the GRM2 gene. mGluR2 is a G protein-coupled receptor (GPCR) that couples with the Gi alpha subunit. The receptor functions as an autoreceptor for glutamate, that upon activation, inhibits the emptying of vesicular contents at the presynaptic terminal of glutamatergic neurons.
Metabotropic glutamate receptor 3 (mGluR3) is an inhibitory Gi/G0-coupled G-protein coupled receptor (GPCR) generally localized to presynaptic sites of neurons. In humans, is encoded by the GRM3 gene.
Metabotropic glutamate receptor 4 is a protein that in humans is encoded by the GRM4 gene.
The 5-HT7 receptor is a member of the GPCR superfamily of cell surface receptors and is activated by the neurotransmitter serotonin (5-hydroxytryptamine, 5-HT) The 5-HT7 receptor is coupled to Gs (stimulates the production of the intracellular signaling molecule cAMP) and is expressed in a variety of human tissues, particularly in the brain, the gastrointestinal tract, and in various blood vessels. This receptor has been a drug development target for the treatment of several clinical disorders. The 5-HT7 receptor is encoded by the HTR7 gene, which in humans is transcribed into 3 different splice variants.
α5IA (LS-193,268) is a nootropic drug invented in 2004 by a team working for Merck, Sharp and Dohme, which acts as a subtype-selective inverse agonist at the benzodiazepine binding site on the GABAA receptor. It binds to the α1, α2, α3 and α5 subtypes.
5-Fluorowillardiine is a selective agonist for the AMPA receptor, with only limited effects at the kainate receptor. It is an excitotoxic neurotoxin when used in vivo and so is rarely used in intact animals, but it is widely used to selectively stimulate AMPA receptors in vitro. It is structurally similar to the compound willardiine, which is also an agonist for the AMPA and kainate receptors. Willardiine occurs naturally in Mariosousa willardiana and Acacia sensu lato.
YM-348 is an indazole derivative drug which acts as a potent and selective 5-HT2C receptor agonist, with an EC50 of 1nM and 15x selectivity over 5-HT2A, although it only has moderate selectivity of 3x over the closely related 5-HT2B receptor. It has thermogenic and anorectic effects in animal studies, making it potentially useful for the treatment of obesity.
N6-Cyclopentyladenosine (CPA) is a drug which acts as a selective adenosine A1 receptor agonist. It has mainly cardiovascular effects with only subtle alterations of behavior. CPA is widely used in scientific research into the adenosine receptors and has been used to derive a large family of derivatives.
UB-165 is a drug which acts as an agonist at neuronal nicotinic acetylcholine receptors being a full agonist of the α3β2 isoform and a partial agonist of the α4β2* isoform. It is used to study the role of this receptor subtype in the release of dopamine and noradrenaline in the brain, and has also been used as a lead compound to derive a number of other selective nicotinic receptor ligands.
AM-630 (6-Iodopravadoline) is a drug that acts as a potent and selective inverse agonist for the cannabinoid receptor CB2, with a Ki of 32.1 nM at CB2 and 165x selectivity over CB1, at which it acted as a weak partial agonist. It is used in the study of CB2 mediated responses and has been used to investigate the possible role of CB2 receptors in the brain. AM-630 is significant as one of the first indole derived cannabinoid ligands substituted on the 6-position of the indole ring, a position that has subsequently been found to be important in determining affinity and efficacy at both the CB1 and CB2 receptors, and has led to the development of many related derivatives.
5-(Nonyloxy)tryptamine is a tryptamine derivative which acts as a selective agonist at the 5-HT1B receptor. Increasing the O-alkoxy chain length in this series gives generally increasing potency and selectivity for 5-HT1B, with highest activity found for the nonyloxy derivative, having a 5-HT1B binding affinity of 1.0 nM, and around 300-fold selectivity over the related 5-HT1A receptor.
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.
O-1269 is a drug that is a diarylpyrazole derivative, related to potent cannabinoid antagonist drugs such as rimonabant and surinabant. However O-1269 and several related drugs were unexpectedly found to act as full or partial agonists at the cannabinoid receptors rather than antagonists, and so produce the usual effects expected of cannabinoid agonists in animal tests, such as sedation and analgesic effects. The N-heptyl homolog O-1270 and the N-propyl homolog O-1399 also act as cannabinoid agonists with similar potency in vivo, despite weaker binding affinity at cannabinoid receptors compared to the pentyl homolog O-1269. Agonist-like and atypical cannabinoid activity has also been observed with a number of related compounds.
AM-2389 is a classical cannabinoid derivative which acts as a potent and reasonably selective agonist for the CB1 receptor, with a Ki of 0.16 nM, and 26x selectivity over the related CB2 receptor. It has high potency in animal tests of cannabinoid activity, and a medium duration of action. Replacing the 1',1'-dimethyl substitution of the dimethylheptyl side chain of classical cannabinoids with cyclopropyl or cyclopentyl results in higher potency than cyclobutyl, but only the cyclobutyl derivatives show selectivity for CB1 over CB2. High selectivity for CB1 over CB2 is difficult to achieve (cf. AM-906, AM-1235), as almost all commonly used CB1 agonists have similar or greater affinity for CB2 than CB1, and the only truly highly selective CB1 agonists known as of 2012 are eicosanoid derivatives such as O-1812.
SN-22 is a chemical compound which acts as a moderately selective agonist at the 5-HT2 family of serotonin receptors, with a Ki of 19nM at 5HT2 subtypes vs 514 nM at 5-HT1A receptors. Many related derivatives are known, most of which are ligands for 5-HT1A, 5-HT6 or dopamine D2 receptors or show SSRI activity.
