Multivariate study of the Open Field Drink Test using undernourished rats and desipramine as an antipanic drug

Approach-avoidance animal models are useful as initial screens for drugs affecting anxiety, but the components of anxiety assessed by these models remain poorly defined. Complex models of evaluation allow more complete inferences than those which are obtained when only one behavior is evaluated. Previous studies demonstrate that the tricyclic-antidepressant desipramine exerts a selective anticonflict effect on adult rats submitted to a protein deprivation schedule at perinatal age, in parameters of spontaneous behavior (elevated plus-maze) and conditioned intake (Geller Seifter). These deprived rats show alterations in noradrenergic neurotransmission that resembled the generalized activation of noradrenergic system displayed by patients suffering from panic attacks. The desipramine anticonflict activity was evaluated by a test of ethological conflict: the Open Field Drink Test, without discarding any behavior a priori under a multivaried approach. This approach has not been considered in previous studies with the open field and antipanic drugs. Considering the four variables selected by factorial analysis, desipramine (10 mg/kg/day) administered IP during just 7 days produced a significant diet x drug interaction which was consistent with previous studies. That interaction was independent of the effects of both treatments on weight or intake and was expressed, on deprived rats, as a decrease in all the behaviors, except for the time of drinking, with respect to the control rats, which displayed, in general, a decrease in all the behaviors except for the frequency of grooming.