1. Neuroscience
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Endogenous opioids in the nucleus accumbens promote approach to high-fat food in the absence of caloric need

  1. Kevin Caref
  2. Saleem M Nicola  Is a corresponding author
  1. Albert Einstein College of Medicine, United States
Research Article
  • Cited 9
  • Views 1,798
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Cite this article as: eLife 2018;7:e34955 doi: 10.7554/eLife.34955

Abstract

When relatively sated, people (and rodents) are still easily tempted to consume calorie-dense foods, particularly those containing fat and sugar. Consumption of such foods while calorically replete likely contributes to obesity. The nucleus accumbens (NAc) opioid system has long been viewed as a critical substrate for this behavior, mainly via contributions to the neural control of consumption and palatability. Here, we test the hypothesis that endogenous NAc opioids also promote appetitive approach to calorie-dense food in states of relatively high satiety. We simultaneously recorded NAc neuronal firing and infused a μ-opioid receptor antagonist into the NAc while rats performed a cued approach task in which appetitive and consummatory phases were well separated. The results reveal elements of a neural mechanism by which NAc opioids promote approach to high-fat food despite the lack of caloric need, demonstrating a potential means by which the brain is biased towards overconsumption of palatable food.

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Article and author information

Author details

  1. Kevin Caref

    Department of Neuroscience, Albert Einstein College of Medicine, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6424-4272
  2. Saleem M Nicola

    Department of Neuroscience, Albert Einstein College of Medicine, New York, United States
    For correspondence
    saleem.nicola@einstein.yu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9582-6312

Funding

National Institutes of Health (DA019473)

  • Saleem M Nicola

Klarman Family Foundation (Pilot Award)

  • Saleem M Nicola

Brain and Behavior Research Foundation (NARSAD Young Investigator Awards)

  • Saleem M Nicola

National Institutes of Health (DA038412)

  • Saleem M Nicola

National Institutes of Health (MH092757)

  • Saleem M Nicola

National Institutes of Health (DA041725)

  • Saleem M Nicola

Klarman Family Foundation (Two Year Award)

  • Saleem M Nicola

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 procedures involving animals were in accordance with the National Institutes of Health Guide for the Care and Use of Laboratory Animals and were approved by the Institutional Animal Care and Use Committee at Albert Einstein College of Medicine (protocols 20100103, 20130204, and 20160206).

Reviewing Editor

  1. Richard D Palmiter, Howard Hughes Medical Institute, University of Washington, United States

Publication history

  1. Received: January 9, 2018
  2. Accepted: March 20, 2018
  3. Accepted Manuscript published: March 27, 2018 (version 1)
  4. Version of Record published: April 17, 2018 (version 2)

Copyright

© 2018, Caref & Nicola

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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