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Opioid peptides, opioid receptors and mechanism of down regulation

Kirti Chaturvedi1

  • 1Biomedical Division, Center of Alcohol Studies, Rutgers, The State University of New Jersey, 84 Lipman Drive, New Brunswick, NJ 08901, USA. chaturvedi@aesop.rutgers.edu

Indian Journal of Experimental Biology
|July 23, 2004
PubMed

Insights

This review explores endogenous opioid peptides and their receptors, detailing their brain distribution and role in opioid tolerance. It discusses receptor down-regulation and the ubiquitin/proteasome system

Area of Science:

  • Neuroscience
  • Pharmacology
  • Molecular Biology

Background:

  • Endogenous opioid peptides and receptors are crucial for understanding the central nervous system.
  • Opioid systems play a significant role in pain perception and reward pathways.
  • Opioid tolerance, a major clinical challenge, necessitates understanding the underlying molecular mechanisms.

Purpose of the Study:

  • To review the biogenesis, distribution, and function of endogenous opioid peptides and their receptors.
  • To elucidate the mechanisms of opioid tolerance, focusing on receptor regulation.
  • To discuss the involvement of the ubiquitin/proteasome system in opioid receptor down-regulation.

Main Methods:

  • Literature review of endogenous opioid peptide research.
  • Analysis of anatomical distribution studies of opioid receptors.
  • Examination of molecular mechanisms of receptor regulation and down-regulation.

Main Results:

  • Detailed description of endogenous opioid peptide discovery and brain distribution.
  • Characterization of multiple opioid receptors and their interactions.
  • Evidence for agonist-induced receptor down-regulation as a cause of opioid tolerance, involving the ubiquitin/proteasome system.

Conclusions:

  • Understanding opioid systems and receptor distribution is key to identifying neuronal networks involved in drug action and adaptation.
  • Receptor down-regulation, potentially mediated by the ubiquitin/proteasome system, is a significant factor in opioid tolerance.
  • This review provides insights into the molecular basis of opioid tolerance.

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