Encounters with aggressive conspecifics enhance the locomotor-activating effects of cocaine in the rat.
Evidence suggests that stress enhances the behavioural actions of cocaine in the rat. Paradoxically, however, encounters with aggressive conspecifics lead to a pattern of cocaine self-administration indicative of a reduced functional impact of the drug. Hence, we examined the effects of aggressive encounters on another behavioural measure-locomotor activity. Encounters between Lister Hooded rats and rats of the aggressive Tryon Maze Dull strain significantly enhanced the locomotor-activating effects of cocaine (20 mg/kg) in the Lister Hooded rats. The results suggest that the discrepant findings derived from self-administration studies are a property of the paradigm rather than a property of the stressor.
Marrow
L P
LP
Department of Psychology, University of Wales Swansea, Singleton Park, Swansea, UK.
Overton
P G
PG
Brain
P F
PF
Clark
D
D