Combined dieting and stress evoke exaggerated responses to opioids in binge-eating rats.
The authors developed an animal model of binge eating where history of caloric restriction with footshock stress (R + S) causes rats to consume twice the normal amount of palatable food. The authors tested the hypothesis that binge eating is mediated by changes in opioid control of feeding by comparing rats' anorectic and orexigenic responses to naloxone and butorphanol, respectively, and by testing the ability of butorphanol to elicit binge eating of chow when palatable food was absent. Mu/kappa opioid-receptor blockade and activation had exaggerated responses in the R + S rats with naloxone suppressing binge eating to control levels, and although butorphanol did not trigger chow binge eating, it enhanced binge eating of palatable food. These responses in sated normal-weight rats strengthen evidence that reward, over metabolic need, drives binge eating.
Boggiano
Mary M
MM
Department of Psychology, Behavioral Neuroscience Division, University of Alabama at Birmingham, AL 35294-1170, USA. boggiano@uab.edu
Chandler
Paula C
PC
Viana
Jason B
JB
Oswald
Kimberly D
KD
Maldonado
Christine R
CR
Wauford
Pamela K
PK
D000701:Analgesics, Opioid / Q000494:pharmacology; D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal; D001835:Body Weight / Q000187:drug effects / Q000502:physiology; D002032:Bulimia / Q000209:etiology*; D002077:Butorphanol / Q000494:pharmacology; D031204:Caloric Restriction / Q000379:methods*; D004195:Disease Models, Animal; D004597:Electroshock / Q000009:adverse effects*; D002149:Energy Intake / Q000187:drug effects / Q000502:physiology; D005247:Feeding Behavior / Q000187:drug effects*; D005260:Female; D005518:Food Preferences / Q000187:drug effects / Q000502:physiology; D009270:Naloxone / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D009294:Narcotics / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D000701:Analgesics, Opioid; D009292:Narcotic Antagonists; D009294:Narcotics; D009270:Naloxone; D002077:Butorphanol