Effects of cat exposure and cat odors on subsequent amphetamine-induced stereotypy.

The effect of exposure to a cat, as a predatory stressor, was examined in male and female rats during subsequent tests of amphetamine-induced stereotypy in which cat odors were present or absent. Rats in Group C/O were given a 15-min exposure session to a male cat while they were protected in a wire cage. They were then given an IP injection of d-amphetamine (1 mg/kg) and tested 30 min later for stereotypy in the presence of cat odors (soiled cat litter). Rats in Group NC/O were given a no-cat-exposure control session, and amphetamine tested with cat odors. Groups C/NO and NC/NO were both tested without cat odors (fresh litter), with the former group having been previously exposed to a cat. During the 90-min test sessions, female rats showed significantly more stereotypy than males. More importantly, the male subjects in group C/O exhibited significantly more stereotypy than the males in the other groups, and group NC/NO males showed the least amount of stereotypy. These findings clearly indicate that amphetamine reactivity is influenced by prior exposure to a predator, the presence of predatory odors during testing, and the subject's sex.