Stress and hunger alter the anorectic efficacy of fluoxetine in binge-eating rats with a history of caloric restriction.
OBJECTIVE
We examined the effect of fluoxetine to suppress binge eating in rats with a history of caloric restriction (CR) and the extent to which this effect was altered by stress and hunger.


METHODS
To detect heightened sensitivity to fluoxetine, young female rats were used to determine a subthreshold anorectic dose (2 mg/kg, intraperitonally). Another group of rats was either fed ad libitum or given multiple CR (to 90% body weight) and refeeding-to-satiety cycles. One half of the rats were then either spared or subjected to foot shock stress before fluoxetine treatment.


RESULTS
A history of CR alone produced bingelike eating on palatable food (p < .001) and, although stress did not affect intake, it rendered CR rats hypersensitive to the satiety effect of fluoxetine. The feeding-suppression was mainly for chow (p < .05) and the effect was abolished if the rats were in negative energy balance.


CONCLUSIONS
Results support the utility of this animal model to elucidate serotonergic changes linking dieting to binge eating. The diverse effects of fluoxetine on the type of food, and in hungry versus sated rats, suggest alternate brain mechanisms should be concomitantly targeted for improved treatment of binge eating disorders.
Placidi
Rachel J
RJ
Department of Psychology, Division of Behavioral Neuroscience, The University of Alabama at Birmingham, Alabama 35294-1170, USA.
Chandler
Paula C
PC
Oswald
Kimberly D
KD
Maldonado
Christine
C
Wauford
Pamela K
PK
Boggiano
Mary M
MM
D000818:Animals; D000855:Anorexia / Q000188:drug therapy*; D002032:Bulimia / Q000139:chemically induced*; D002149:Energy Intake / Q000187:drug effects*; D005260:Female; D005473:Fluoxetine / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use*; D006815:Hunger; D007274:Injections, Intraperitoneal; D051381:Rats; D017207:Rats, Sprague-Dawley; D017367:Selective Serotonin Reuptake Inhibitors / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use*; D013315:Stress, Psychological / Q000523:psychology*
D005473:Fluoxetine; D017367:Selective Serotonin Reuptake Inhibitors