mTORC1 in the orbitofrontal cortex promotes habitual alcohol seeking

  1. Nadege Morisot
  2. Khanhky Phamluong
  3. Yann Ehinger
  4. Anthony L Berger
  5. Jeffrey J Moffat
  6. Dorit Ron  Is a corresponding author
  1. University of California, San Francisco, United States

Abstract

The mechanistic target of rapamycin complex 1 (mTORC1) plays an important role in dendritic translation and in learning and memory. We previously showed that heavy alcohol use activates mTORC1 in the orbitofrontal cortex (OFC) of rodents (1). Here, we set out to determine the consequences of alcohol-dependent mTORC1 activation in the OFC. We found that inhibition of mTORC1 activity attenuates alcohol seeking and restores sensitivity to outcome devaluation in rats that habitually seek alcohol. In contrast, habitual responding for sucrose was unaltered by mTORC1 inhibition, suggesting that mTORC1's role in habitual behavior is specific to alcohol. We further show that inhibition of GluN2B in the OFC attenuates alcohol-dependent mTORC1 activation, alcohol seeking and habitual responding for alcohol. Together, these data suggest that the GluN2B/mTORC1 axis in the OFC drives alcohol seeking and habit.

Data availability

Source data flles have been provided for Figures 1-5

Article and author information

Author details

  1. Nadege Morisot

    Department of Neurology, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Khanhky Phamluong

    Department of Neurology, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Yann Ehinger

    Department of Neurology, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Anthony L Berger

    Department of Neurology, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Jeffrey J Moffat

    Department of Neurology, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Dorit Ron

    Department of Neurology, University of California, San Francisco, San Francisco, United States
    For correspondence
    dorit.ron@ucsf.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5161-967X

Funding

National Institute on Alcohol Abuse and Alcoholism (P50 AA017072)

  • Dorit Ron

National Institute on Alcohol Abuse and Alcoholism (R01 AA027474)

  • Dorit Ron

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 procedures were approved by the University of California San Francisco Institutional Animal Care and Use Committee (IACUC) and were conducted in agreement with the Association for Assessment and Accreditation of Laboratory Animal Care (AAALAC).(protocol number number AN179720-01B),

Reviewing Editor

  1. Mary Kay Lobo, University of Maryland, United States

Publication history

  1. Received: August 25, 2019
  2. Accepted: December 9, 2019
  3. Accepted Manuscript published: December 10, 2019 (version 1)
  4. Accepted Manuscript updated: December 11, 2019 (version 2)
  5. Version of Record published: January 14, 2020 (version 3)
  6. Version of Record updated: May 4, 2022 (version 4)

Copyright

© 2019, Morisot 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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  1. Nadege Morisot
  2. Khanhky Phamluong
  3. Yann Ehinger
  4. Anthony L Berger
  5. Jeffrey J Moffat
  6. Dorit Ron
(2019)
mTORC1 in the orbitofrontal cortex promotes habitual alcohol seeking
eLife 8:e51333.
https://doi.org/10.7554/eLife.51333

Further reading

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