Endogenous opioids in the nucleus accumbens promote approach to high-fat food in the absence of caloric need
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.
Data availability
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Data from: Endogenous opioids in the nucleus accumbens promote approach to high-fat food in the absence of caloric needAvailable at Dryad Digital Repository under a CC0 Public Domain Dedication.
Article and author information
Author details
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).
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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