Gender differences in the effects of haloperidol on avoidance conditioning in mice

Gender differences in the effects of haloperidol (0.075 mg/kg per day for 5 days) on avoidance conditioning were evaluated. We also studied performance of the subjects free of the drug and the acute effects of haloperidol in animals trained without drug 48 h after the last haloperidol administration. Latencies of escape and avoidance responses, number of nonresponses, escapes, avoidances, crossings during the adaptation period, crossings during intertrial intervals, and total crossings per minute were analyzed. This dosage impaired conditioning of the male animals but did not attain the same effects on females. Haloperidol did not deteriorate performance of the task when it had been learned previously without drug. The results confirm the existence of gender differences in haloperidol effects on avoidance conditioning in mice and suggest that these differences are related to the learning process and not only to the impairment of motor behavior characteristic of neuroleptic drugs.