Symbol GPR172A HUGO 30224 RefSeq NM_024531 | Entrez 79581 OMIM 607882 UniProt Q9HAB3 | |
The γ-hydroxybutyrate (GHB) receptor (GHBR), originally identified as GPR172A, is a G protein-coupled receptor (GPCR) that binds the neurotransmitter and psychoactive drug γ-hydroxybutyric acid (GHB).
Contents
History
The existence of a specific GHB receptor was predicted by observing the action of GHB and related compounds that primarily act on the GABAB receptor, but also exhibit a range of effects which were found not to be produced by GABAB activity, and so were suspected of being produced by a novel and at the time unidentified receptor target. Following the discovery of the "orphan" G-protein coupled receptor GPR172A, it was subsequently found to be the GHB receptor whose existence had been previously predicted. The rat GHB receptor was first cloned and characterised in 2003 followed by the human receptor in 2007.
Function
The function of the GHB receptor appears to be quite different from that of the GABAB receptor. It shares no sequence homology with GABAB, and administration of mixed GHB/GABAB receptor agonists along with a selective GABAB antagonist or selective agonists for the GHB receptor which are not agonists at GABAB, do not produce a sedative effect, instead causing a stimulant effect followed by convulsions at higher doses, thought to be mediated through increased Na+/K+ current and increased release of dopamine and glutamate.