Trafficking of central opioid receptors and descending pain inhibition.
The delta-opioid receptor (DOR) belongs to the superfamily of G-protein-coupled receptors (GPCRs) with seven transmembrane domains, and its membrane trafficking is regulated by intracellular sorting processes involving its C-tail motifs, intracellular sorting proteins, and several intracellular signaling pathways. In the quiescent state, DOR is generally located in the intracellular compartments in central neurons. However, chronic stimulation, such as chronic pain and sustained opioid exposure, may induce membrane trafficking of DOR and its translocation to surface membrane. The emerged functional DOR on cell membrane is actively involved in pain modulation and opioid analgesia. This article reviews current understanding of the mechanisms underlying GPCRs and DOR membrane trafficking, and the analgesic function of emerged DOR through membrane trafficking under certain pathophysiological circumstances.
Department of Anesthesiology and Pain Medicine, The University of Texas-MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA. bbie@mdanderson.org
Bihua
B
Bie
Zhizhong Z
ZZ
Pan
D000818:Animals; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D010146:Pain / Q000188:drug therapy / Q000378:metabolism / Q000503:physiopathology*; D021381:Protein Transport / Q000187:drug effects; D011957:Receptors, Opioid / Q000378:metabolism*
D011957:Receptors, Opioid