An animal model for the study of binge-like eating episodes preceded by frustration events in females and non-food deprived animals

Introduction: Previous data from our laboratory show that frustration events could function as an important factor in the etiology and maintenance of the binge-like eating episodes. However, in previous experiments, male Wistar rats deprived of food were used. This reduced the external validity of the phenomenon as an animal model of binge-eating episodes since they are more prevalent in women and can occur without prior energy deficit. Objective: To explore the presence of increased intake after a previous frustration event in two new experimental conditions: male rats without food deprivation (experiment 1) and female rats with food deprivation at 83% of their ad libitum weight (experiment 2). Method: The animals had access to a 32% sweetened solution during five daily trials of five minutes each. During the trials 6, 8 and 10, half of the animals received the reinforcer normally, and the other half after a delay of 10 min. In the trials 7, 9 and 11 all animals received the reward without prior delay. Results: The model was replicated in the two experiments. Discussion: These data generalize our previous observations to two novel conditions, one sexual and the other motivational, which results in an increase in its external validity.