Related Experiment Video

Updated: Aug 24, 2026

Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
07:23

Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities

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[Opioid tolerance: what if it was just a question of receptor internalization?]

Nicolas Marie1, Philippe Jauzac, Stéphane Allouche

  • 1Laboratoire de Pharmacologie Moléculaire de la Tolérance aux Opiacés, Centre Hospitalier et Universitaire de Caen, Université de Caen, France.

Annales De Medecine Interne
|February 5, 2004
PubMed

Insights

Opioid agonists effectively relieve pain but cause tolerance, a major limitation. Receptor internalization and sorting are key steps in opioid receptor desensitization, contributing to this tolerance development.

Area of Science:

  • Pharmacology
  • Molecular Biology
  • Neuroscience

Context:

  • Opioid agonists are vital for pain management but chronic use leads to tolerance.
  • Opioid receptor desensitization is a critical mechanism underlying tolerance.
  • Understanding these molecular processes is essential for improving pain therapies.

Purpose:

  • To review the molecular mechanisms of opioid receptor desensitization.
  • To highlight the role of receptor internalization and sorting in tolerance.
  • To provide insights into the cellular events following opioid receptor activation.

Summary:

  • Opioid receptor desensitization, involving phosphorylation, internalization, and degradation, is central to tolerance.
  • Receptor internalization and subsequent sorting pathways are crucial for modulating opioid signaling.
  • Cellular models reveal complex protein interactions and trafficking events in desensitization.

Impact:

  • Informs the development of strategies to mitigate opioid tolerance.
  • Enhances understanding of drug side effects and therapeutic limitations.
  • Contributes to the design of more effective and safer analgesics.

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