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Opioid receptor heteromers in analgesia

Published online by Cambridge University Press:  10 April 2012

Cristina M. Costantino
Affiliation:
Department of Pharmacology and Systems Therapeutics, The Friedman Brain Institute, Mount Sinai School of Medicine, New York, NY, USA
Ivone Gomes
Affiliation:
Department of Pharmacology and Systems Therapeutics, The Friedman Brain Institute, Mount Sinai School of Medicine, New York, NY, USA
Steven D. Stockton Jr
Affiliation:
Department of Pharmacology and Systems Therapeutics, The Friedman Brain Institute, Mount Sinai School of Medicine, New York, NY, USA Department of Neuroscience, The Friedman Brain Institute, Mount Sinai School of Medicine, New York, NY, USA
Maribel P. Lim
Affiliation:
Department of Pharmacology and Systems Therapeutics, The Friedman Brain Institute, Mount Sinai School of Medicine, New York, NY, USA
Lakshmi A. Devi*
Affiliation:
Department of Pharmacology and Systems Therapeutics, The Friedman Brain Institute, Mount Sinai School of Medicine, New York, NY, USA Department of Neuroscience, The Friedman Brain Institute, Mount Sinai School of Medicine, New York, NY, USA
*
*Corresponding author: Lakshmi A. Devi, 1468, Madison Avenue, New York, NY 10029USA. E-mail: Lakshmi.devi@mssm.edu

Abstract

Opiates such as morphine and fentanyl, a major class of analgesics used in the clinical management of pain, exert their effects through the activation of opioid receptors. Opioids are among the most commonly prescribed and frequently abused drugs in the USA; however, the prolonged use of opiates often leads to the development of tolerance and addiction. Although blockade of opioid receptors with antagonists such as naltrexone and naloxone can lessen addictive impulses and facilitate recovery from overdose, systemic disruption of endogenous opioid receptor signalling through the use of these antagonistic drugs can have severe side effects. In the light of these challenges, current efforts have focused on identifying new therapeutic targets that selectively and specifically modulate opioid receptor signalling and function so as to achieve analgesia without the adverse effects associated with chronic opiate use. We have previously reported that opioid receptors interact with each other to form heteromeric complexes and that these interactions affect morphine signalling. Since chronic morphine administration leads to an enhanced level of these heteromers, these opioid receptor heteromeric complexes represent novel therapeutic targets for the treatment of pain and opiate addiction. In this review, we discuss the role of heteromeric opioid receptor complexes with a focus on mu opioid receptor (MOR) and delta opioid receptor (DOR) heteromers. We also highlight the evidence for altered pharmacological properties of opioid ligands and changes in ligand function resulting from the heteromer formation.

Type
Review Article
Copyright
Copyright © Cambridge University Press 2012

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