Succinate receptor GPR91, a Gαi coupled receptor that increases intracellular calcium concentrations through PLCβ

Succinate has been reported as the endogenous ligand for GPR91. In this study, succinate was confirmed to activate GPR91 resulting in both 3'-5'-cyclic adenosine monophosphate (cAMP) inhibition and inositol phosphate formation in a pertussis toxin (PTX)-sensitive manner. GPR91 agonist-mediated effects detected using dynamic mass redistribution (DMR) were inhibited with PTX, edelfosine and U73122 demonstrating the importance of not only the G alpha(i) pathway but also PLC beta. These results show that GPR91 when expressed in HEK293s cells couples exclusively through the G alpha(i) pathway and acts through G alpha(i) not only to inhibit cAMP production but also to increase intracellular Ca2+ in an inositol phosphate dependent mechanism via PLC beta activation. (C) 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.