Cafeteria diet decreases sucrose preference and increases the sensitivity of risperidone in the caloric intake of Wistar rats

Abstract
The purpose of this study was to evaluate the increase in sensitivity of a single risperidone administration in relation to energy intake of Wistar rats treated with cafeteria diet from birth to adulthood (119 days). During the lactation period, six litters of Wistar rats (dam + 8 pups each litter) were fed one of the following two diets: Control (n = 3) or Cafeteria (n = 3) diets and water ad libitum. After weaning, the males were placed in individual cages, receiving the same diet offered to their respective dams (Control = 18; or Cafeteria = 18) until adulthood (119 postnatal days). The following parameters were evaluated: food and energy intake; macronutrient intake; weight gain; adipose tissue relative weight; sucrose preference; food intake after an administration of risperidone (0.1 mg/kg body weight). The Cafeteria group showed a higher energy intake in relation to the Control group (p < 0.001). The consumption of energy beyond the individual needs can be understood as a hyperphagic condition. Also, the Cafeteria group reported greater weight gain (p = 0.048) and accumulation of adipose tissue (p < 0.001) with respect to the Control group. These results indicate that the cafeteria diet generated obesity in animals. The Cafeteria group showed reduced sucrose preference (p = 0.031), which is associated with the development of anhedonia-like behavior. In the food intake test, risperidone showed a greater sensitivity in Cafeteria animals, promoting a decrease in their energy intake in relation to the Control group that received risperidone (p = 0.040). The cafeteria diet promoted hyperphagia, anhedonia-like behavior and obesity in animals. Acute risperidone administration showed greater sensitivity in the Cafeteria group, with a decrease in energy intake. The reported effects may be related to a downregulation of the dopaminergic system in the NAc region.