First Author | Kern A | Year | 2012 |
Journal | Neuron | Volume | 73 |
Issue | 2 | Pages | 317-32 |
PubMed ID | 22284186 | Mgi Jnum | J:182302 |
Mgi Id | MGI:5315199 | Doi | 10.1016/j.neuron.2011.10.038 |
Citation | Kern A, et al. (2012) Apo-ghrelin receptor forms heteromers with DRD2 in hypothalamic neurons and is essential for anorexigenic effects of DRD2 agonism. Neuron 73(2):317-32 |
abstractText | We identified subsets of neurons in the brain that coexpress the dopamine receptor subtype-2 (DRD2) and the ghrelin receptor (GHSR1a). Combination of FRET confocal microscopy and Tr-FRET established the presence of GHSR1a:DRD2 heteromers in hypothalamic neurons. To interrogate function, mice were treated with the selective DRD2 agonist cabergoline, which produced anorexia in wild-type and ghrelin/ mice; intriguingly, ghsr/ mice were refractory illustrating dependence on GHSR1a, but not ghrelin. Elucidation of mechanism showed that formation of GHSR1a:DRD2 heteromers allosterically modifies canonical DRD2 dopamine signaling resulting in Gbetagamma subunit-dependent mobilization of [Ca(2)](i) independent of GHSR1a basal activity. By targeting the interaction between GHSR1a and DRD2 in wild-type mice with a highly selective GHSR1a antagonist (JMV2959) cabergoline-induced anorexia was blocked. Inhibiting dopamine signaling in subsets of neurons with a GHSR1a antagonist has profound therapeutic implications by providing enhanced selectivity because neurons expressing DRD2 alone would be unaffected. |