CHANGES IN D-AMPHETAMINE ELICITED ROTATIONAL BEHAVIOR IN RATS EXPOSED TO UNCONTROLLABLE FOOTSHOCK STRESS

Male and female rats, selected on the basis of their rotational behavior in response to d-amphetamine, were exposed to either escapable footshock stress, inescapable footshock stress or no stress and were than given a shuttlebox escape task on the subsequent day. Following testing, the magnitude and direction of the animals'' rotational responses to d-amphetamine were determined again. Inescapable footshock stress induced a selective change in the direction and intensity of rotational behavior that was dependent upon the subjects'' sex and preexisting rotational bias. Right-rotating males and left-rotating females shifted their directional bias toward the opposite side, while left-rotating males and right-rotating females displayed increased rotation in their pre-stress direction. Significant correlations were also noted between the intensity of pre-stress rotational behavior and performance on the shuttlebox shock escape task. The results are discussed with respect to stress'' actions on the mesocortical dopamine system and how this system''s sex-dependent asymmetrical organization may subserve part of the organism''s general reaction to uncontrollable stress.