Study of the impact of ghrelin receptor dimerization with other G-protein coupled receptors on calcium channel modulation

MUSTAFÁ ER; CORDISCO GONZALEZ S; LÓPEZ SOTO EJ; RODRÍGUEZ S; RAINGO J

Huerta Grande, Cordoba

Congreso; XXIX CONGRESO ANUAL DE LA SOCIEDAD ARGENTINA DE INVESTIGACION EN NEUROCIENCIAS; 2014

Growth hormone secretagogue receptor type 1a (GHSR1a) activity modulates neuronal circuits that control appetite and energy expenditure. GHSR1a is a G protein-coupled receptor prone to constitutive and ligand-evoked activation. It has been described that GHSR1a can form dimers with other G protein coupled receptors, the melanocortin receptor type 3 (MCR3) and the dopamine receptor type 2 (D2R) and that this interaction affects the signaling of both receptors. Presynaptic voltage gated calcium channels (VGCC) are very sensitive to G protein mediated pathways and this regulation impacts on synaptic transmission. Here we aimed to understand how dimerization between GHSR1a and MC3R or D2R modifies VGCC inhibition by these receptors activity. We found that co-expression of MC3R negatively impacts on GHSR1a constitutive activity mediated inhibition of VGCC (Type CaV2.2) while D2R co-expression has no effect. On the other hand we found that dopamine mediated inhibition of VGCC remains unchanged when GHSR1a is co-expressed. Our data suggest that dimerization of GHSR1a with other physiological relevant receptors could impact on VGCC modulation.