Study On The Dimer Of μopioid Receptor And Oxytocin Receptor

Morphine can take lots of pharmacological roles including analgesis, modification of immunal function and neuroendocrine. The signal pathway mediated by μopioid receptor (MOR) is the main machenism of morphine effects. However, some effects of morphine such as inhibition of oxytcoin synthesis and releases induced by chronic morphine treatment have been explicated by the mechanism.Both MOR and oxytocin receptor (OTR) belong to G protein coupled receptors (GPCRs) family A and can form homodimers/oligomers and heterodimers. To explore the molecular machenism of morphine inhibitting effect on oxytocin synthesis and secretion, the methods of biochemistry and biophysiology were used to examine whether there was direct interaction between MOR and OTR, which could provide a new pathway of morphine and the molecular experimental data to apply opioid medicines powerfully.Firstly the peptide including N-terminal amino acid residue 1 -86 of MOR that fused with thioredoxin A protein was expressed and purified, then the peptide was used as antigen to produce MOR antibody(MOR-Ab). The speciality of MOR-ab was tested with western blot and fluorescent-immunohistochemistry. After plasmid pcDNA3.1-MOR and pcDNA3.1-OTR were co-transfected into CHO cell, the expression of protein MOR and OTR was confirmed with fluerescent-immunocytochemistry. Immunoprecipitation was used to investigate the heterodimerization of MOR and OTR in the cultrued cell and rat brain lysis, and in the biophysiology the spatial distribution of MOR and OTR in cells could further identify the MOR-OTR heterodimer.The results showed that MOR and OTR formed heterodimer in the co-transfected CHO cells and rat brain.