Prefrontal and striatal dopamine metabolism during enhanced rebound hyperphagia induced by space restriction - A rat model of binge eating

Background: Several lines of evidence indicate that abnormalities in brain dopamine and serotonin metabolism may play an important role in bulimia ner vosa. However, the regional neurochemical mechanism of the binge eating is poorly understood. Our purpose was to elucidate brain neurochemical mechani sms of binge eating using a rat model. Methods: The dopamine release and metabolism in the prefrontal cortex (PFC) and in the ventrolateral striatum (VLS) of rats were studied using microdi alysis during enhanced rebound hyperphagia induced by space restriction (an animal model of binge eating). Results: The rats showed rebound hyperphagic state when they were released from scheduled feeding (2 hours/day feeding for 7 days). The hyperphagia wa s further enhanced when they were put in a space-restricted cage where thei r mobility was restricted. Dopamine release and metabolism were increased b oth in the PFC and in the VLS during the enhanced rebound hyperphagia. Conclusions: These results tentatively suggest that increased dopamine rele ase and metabolism in the PFC and in the VLS may be related to space restri ction and to activation of motor function involved in feeding behavior, res pectively. The enhanced rebound hyperphagia induced by space restriction ma y be useful as an animal model of binge eating. Biol Psychiatry 1998;44:132 9-1336 (C) 1998 Society of Biological Psychiatry.