Food deprivation history and cocaine self-administration: an animal model of binge eating.

In this two-part study, an animal model of binge eating was first produced, then the rate of acquisition of cocaine self-administration was assessed. Initially, 16 female weanling rats were food deprived (DEPR) at 25, 95, and 143 days of age. Another group of 16 age-matched controls was allowed ad lib access to food. Each time the DEPR group was food deprived, they were allowed to recover to normal weight. They were then injected with butorphanol tartrate (BUTR), an opioid that stimulates feeding, and food intake was measured for 4 h. All rats given BUTR consumed significantly more food than those given saline. Animals with DEPR history consumed food over a longer period of time, and at h 4 after BUTR injection, they consumed significantly more food than controls. In the second part of the experiment, an autoshaping procedure was used to quantitatively evaluate the rate of acquisition of cocaine self-administration. By day 30, 86% of the DEPR and 69% of the control groups had acquired cocaine self-administration.