G Protein-Coupled Receptor Kinase 5 (GRK5) Modulates Nociceptin/Orphanin FQ Opioid (NOP) Receptor Desensitization in Rat Sympathetic Neurons.

ABSTRACT: Stimulation of nociceptin/orphanin FQ peptide (NOP) opioid receptors by the endogenous ligand nociceptin (Noc) leads to voltage-gated Ca²⁺ channel inhibition or G protein inwardly rectifying K⁺ channel activation. One mechanism of G protein-coupled receptor (GPCR) desensitization occurs when G protein-coupled receptor kinases (GRK) phosphorylate the agonist-bound receptors. In the continued presence of an agonist, Gβγ recruits GRK to the plasma membrane where GPCR are then phosphorylated by GRK. The purpose of this study was to identify the GRK subtype responsible for desensitization of the Noc-mediated Ca²⁺ current inhibition in rat stellate ganglion (SG) neurons. We observed that GRK2 and GRK5 are expressed in SG neurons. Further, silencing either GRK sub

SUBMITTER: Farrag M 

PROVIDER: S-EPMC12800729 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature