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ß-arrestin 2 germline knockout does not attenuate opioid respiratory depression

  1. Iris Bachmutsky
  2. Xin Paul Wei
  3. Adelae Durand
  4. Kevin Yackle  Is a corresponding author
  1. University of California, San Francisco, United States
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Cite this article as: eLife 2021;10:e62552 doi: 10.7554/eLife.62552

Abstract

Opioids are perhaps the most effective analgesics in medicine. However, between 1999 to 2018, over 400,000 people in the United States died from opioid overdose. Excessive opioids make breathing lethally slow and shallow, a side-effect called opioid induced respiratory depression. This doubled-edged sword has sparked the desire to develop novel therapeutics that provide opioid-like analgesia without depressing breathing. One such approach has been the design of so-called 'biased agonists' that signal through some, but not all pathways downstream of the µ-opioid receptor (MOR), the target of morphine and other opioid analgesics. This rationale stems from a study suggesting that MOR-induced ß-arrestin 2 dependent signaling is responsible for opioid respiratory depression, whereas adenylyl cyclase inhibition produces analgesia. To verify this important result that motivated the 'biased agonist' approach, we re-examined breathing in ß-arrestin 2 deficient mice and instead find no connection between ß-arrestin 2 and opioid respiratory depression. This result suggests that any attenuated effect of 'biased agonists' on breathing is through an as-yet defined mechanism.

Data availability

The data generated in Figures 2-4 are provided in the source files.

Article and author information

Author details

  1. Iris Bachmutsky

    Department of Physiology, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Xin Paul Wei

    Department of Physiology, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Adelae Durand

    Department of Physiology, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Kevin Yackle

    Department of Physiology, University of California, San Francisco, San Francisco, United States
    For correspondence
    Kevin.Yackle@ucsf.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1870-2759

Funding

NIH Office of the Director (DP5-OD023116)

  • Kevin Yackle

Program for Breakthrough Biomedical Research

  • Kevin Yackle

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: All animal experiments were performed in accordance with national and institutional guidelines with standard precautions to minimize animal stress and the number of animals used in each experiment. All animal protocols have been approved by the UCSF 'Office of Research'.approval number AN181239.

Reviewing Editor

  1. Allan Basbaum, University of California San Francisco, United States

Publication history

  1. Received: August 28, 2020
  2. Accepted: May 17, 2021
  3. Accepted Manuscript published: May 18, 2021 (version 1)
  4. Accepted Manuscript updated: May 24, 2021 (version 2)

Copyright

© 2021, Bachmutsky et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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