The behavior of protein-calorie-malnourished rats on the elevated plus- maze test: An ethopharmacological analysis

Abstract

In order to study the effects of the protein-calorie malnutrition on the behavior of rats submitted to the elevated plus-maze, an ethopharmacological analysis was used. Litters (dam plus 6 male pups) were fed ad lib (control) or were fed 50% of the amount of diet consumed by the control group (malnourished) from birth to 49 days of age. From Day 50 on, all rats were fed ad lib. At 70 days of age, the animals were pharmacologically treated (vehicle or diazepam, 1.5 and 3.0 mg/kg) and were placed, 30 min later, in the center of the elevated plus-maze for a 5-min session. During this session, 11 behaviors believed to indicate anxiety or exploration were measured. The results showed that protein-calorie malnutrition results in increased exploration of the open arms of the maze, higher latency of first ann entry, and lower closed-arm returns, indicating lower anxiety or higher impulsiveness. In addition, the protein-calorie-malnourished rats were hyporeactive to the anxiolytic effects of diazepam, indicating possible alterations in the GABA-benzodiazepine system as result of the malnutrition procedure.