Entrez 2912 | Ensembl ENSG00000164082 | |
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Aliases GRM2, GPRC1B, MGLUR2, mGlu2, glutamate metabotropic receptor 2, mGluR2 External IDs MGI: 1351339 HomoloGene: 20229 GeneCards: GRM2 |
Function
L-glutamate is the major excitatory neurotransmitter in the central nervous system and activates both ionotropic and metabotropic glutamate receptors. Glutamatergic neurotransmission is involved in most aspects of normal brain function and can be perturbed in many neuropathologic conditions. The metabotropic glutamate receptors are a family of G protein-coupled receptors, that have been divided into 3 groups on the basis of sequence homology, putative signal transduction mechanisms, and pharmacologic properties. Group I includes GRM1 and GRM5 and these receptors have been shown to activate phospholipase C. Group II includes GRM2 (this receptor) and GRM3 while Group III includes GRM4, GRM6, GRM7 and GRM8. Group II and III receptors are linked to the inhibition of the cyclic AMP cascade but differ in their agonist selectivities.
Role in hallucinogenesis
Many psychedelic drugs (e.g. LSD-25) produce their effects by binding to the oligomerized complexes of the 5HT2A and mGlu2 receptors. Lisuride acts preferentially or exclusively on the non-heteromerized 5HT2A receptors, which are not capable of inducing psychedelic effects. Due to this, lisuride is capable of reducing the hallucinogenic effects of these drugs through competitive agonistic activity (producing the effect of a silent-agonist in the presence of these drugs).
Strong agonists for either subunit of the 5HT2A-mGlu2R heterocomplex suppress signaling through the partner subunit and inverse agonists for either subunit potentiate the signaling through the partner subunit.
Ligands
The development of subtype-2-selective positive allosteric modulators (PAMs) experienced steady advance in recent years. mGluR2 potentiation is a new approach for the treatment of schizophrenia. On the other hand, antagonists and negative allosteric modulators of mGluR2/3 have potential as antidepressant drugs.
Agonists
PAMs
Antagonists
NAMs
Protein–protein interactions
The metabotropic glutamate receptor 2 is able to form a heteromeric complex with its isoform mGluR4. This heteromer exhibits a pharmacological profile distinct from the parent receptor monomers.