Chronic Intermittent Sucrose Consumption Facilitates the Ability to Discriminate Opioid Receptor Blockade with Naltrexone in Rats. Nutrients 2022 Feb 22;14(5)
Date
03/11/2022Pubmed ID
35267900Pubmed Central ID
PMC8912831DOI
10.3390/nu14050926Scopus ID
2-s2.0-85125184551 (requires institutional sign-in at Scopus site) 3 CitationsAbstract
The opioid antagonist naltrexone (NTX) decreases intake of preferred diets in rats at very low doses relative to doses needed to decrease intake of "bland" laboratory chow. In the absence of an opioid agonist, NTX is not discriminable using operant techniques. In the current study, we found that rats given intermittent access to a 25% sucrose solution learned to discriminate between various naltrexone doses and saline. None of the rats given only water learned to discriminate between naltrexone and saline. When access to the sucrose solution was discontinued for 14 days, the rats lost the ability to discriminate between NTX and saline. We also studied the changes of c-Fos IR in selected brain regions in rats treated with saline versus NTX that were drinking water or 25% sucrose. An injection of NTX or saline resulted in a significant drug, diet, and interaction effect in various brain regions associated with feeding behavior, particularly the amygdala, accumbens, and hypothalamic sites. Thus, we found that ingestion of a sucrose solution results in the ability of rats to reliably discriminate naltrexone administration. In addition, sucrose and naltrexone altered c-Fos IR in an interactive fashion in brain regions known to be involved in ingestion behavior.
Author List
Jewett DC, Liyanagamage DSNK, Avond MAV, Anderson MAB, Twaroski KA, Marek MA, James KF, Pal T, Klockars A, Olszewski PK, Levine ASAuthor
Mark A. Vanden Avond Research Scientist I in the Physiology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsFeeding Behavior
Naltrexone
Narcotic Antagonists
Rats
Receptors, Opioid
Sucrose
