title: The role of palatable food and hunger as trigger factors in an animal model of stress induced binge eating.
abstract: OBJECTIVE
  Dieting and stress are etiological factors in eating disorders, and dieting strongly predicts stress-induced overeating in the nonclinical population. We developed an animal model of binge eating in sated rats that is evoked by stress, but only in rats with a history of caloric restriction and only if highly palatable food (HPF) is available after stress. This study investigated the effect of known binge triggers, a taste of HPF and of hunger, on this type of binge eating.
  
  
  METHODS
  Female rats were cycled through the R/S protocol but this time were given just a taste of HPF with ad lib regular chow. After another R/S cycle, rats were stressed during restriction (while hungry) and were given HPF and chow.
  
  
  RESULTS
  Although binge eating did not occur if only chow was available after stress, just a taste of HPF sufficed to increase chow intake to more than 160% (p < 0.001) of rats with a history of restriction only, stress-only, or neither. Hunger increased the proportion of chow consumed by both restricted groups, but stress magnified this hunger-induced overeating by increasing HPF intake to 137% of restriction-only rats (p < 0.001).
  
  
  CONCLUSIONS
  These effects suggest that binge eating in this model is motivated by reward, not metabolic need, and parallels observations of binge triggers described in clinical binge-eating disorders. This strengthens the validity of using this animal model to target the physiology and treatment of eating disorders preceded by dieting and stress.
authors.affiliation: Department of Psychology, Behavioral Neuroscience Division, University of Alabama at Birmingham, 35294-1170, USA. mhagan@uab.edu
authors.forename: Mary M
authors.initials: MM
authors.lastname: Hagan
authors.forename: Paula C
authors.initials: PC
authors.lastname: Chandler
authors.forename: Pamela K
authors.initials: PK
authors.lastname: Wauford
authors.forename: Rachel J
authors.initials: RJ
authors.lastname: Rybak
authors.forename: Kimberly D
authors.initials: KD
authors.lastname: Oswald
mesh_terms: D000818:Animals; D002032:Bulimia / Q000523:psychology*; D004195:Disease Models, Animal; D002149:Energy Intake; D005260:Female; D005508:Food Deprivation; D005518:Food Preferences / Q000523:psychology*; D006801:Humans; D006815:Hunger; D009042:Motivation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013315:Stress, Psychological / Q000150:complications*; D013649:Taste