Cocaine produces panic-like flight responses in mice in the mouse defense test battery

There is an emerging body of clinical evidence that cocaine use in humans c an result in serious fear or panic-related emotional disturbances. The pres ent study evaluated the effects of cocaine administration upon defensive re sponses of mice to a predator (rat) in a Mouse Defense Test Battery (MDTB) that permits the display of the full range of the mouse defensive behaviors : avoidance/escape, night, freezing, defensive upright, and defensive threa t and attack. Mice were tested 30 min following intraperitoneal (IP) inject ions of either 0, 10, 20, or 30 mg/kg cocaine hydrochloride suspended in ph ysiological saline. Cocaine produced an increase in flight and escape respo nses throughout the subtests comprising the MDTB. The percentage of subject s exhibiting escape increased in cocaine-treated mice in the Predator Avoid ance Test. Cocaine increased mean flight speed and maximum flight speed in the Flight/Chase Test; frequency of flight responses in the Straight Alley Test; and the number of flight attempts in the Forced Contact test. The pre dominance of flight responding throughout the tests masked any possible coc aine effects on other defenses. The present findings indicate that cocaine may exert its panic-producing effects by acting upon particular neurobehavi oral systems subserving defensive behavior. (C) 1999 Elsevier Science Inc.