Item Details

title

Effects of Nucleus Accumbens Opioids on Intake of Combinations of Palatable Macronutrients

author

Wilson, Lindsey

abstract

Hyperpalatable foods containing combinations of palatable ingredients like sugar and fat are ubiquitous in modern food systems, contributing to increasing rates of obesity. These combinations are favored by humans, and intake of these diets in rodents has been linked with activity in reward circuits. However, it remains poorly understood whether rats prefer sugar and fat blended in some proportions more strongly than others, or how µ-opioid signaling in the nucleus accumbens (NAc), an important region for regulating palatable food intake, affects these preferences. To answer these questions, I tested two cohorts of rats in a novel diet choice paradigm in which they were given concurrent access to six diets composed of systematically varying proportions of sugar and fat. Animals then received either systemic or intra-NAc opioid manipulations to determine the effects of these manipulations on preferences. My results show mixed support for the idea that animals prefer blend diets over pure macronutrients, and are consistent with a role for NAc µ-opioids as strengthening pre-existing taste preferences. This suggests that opioid signaling within the NAc, perhaps in response to homeostatic need, increases food intake by boosting consummatory drive for diets that are already known to be palatable.

subject

Eating behavior

Hyperpalatable foods

Motivation

Nucleus accumbens

Opioids

Palatable feeding

contributor

Pratt, Wayne E (advisor)

Blumenthal, Terry D (committee member)

Maffeo, Melissa L (committee member)

Lack, Anna K (committee member)

date

2024-02-13T09:36:05Z (accessioned)

2023 (issued)

degree

Psychology (discipline)

embargo

2026-02-12 (terms)

2026-02-12 (liftdate)

identifier

http://hdl.handle.net/10339/102906 (uri)

language

en (iso)

publisher

Wake Forest University

type

Thesis