Dose dependency of sex differences in the effects of repeated haloperidol administration in avoidance conditioning in mice.

Sex differences in the effects of haloperidol in active avoidance conditioning in mice have previously been found in various studies carried out in our laboratory. Males were more affected than females by the disruptive effects of this neuroleptic. The work described here broadens the study of these sex differences to higher doses of haloperidol (0.1 and 0.2 mg/kg) using a repeated administration schedule (5 days). The results did not show sex differences in the deteriorating effects of this dopamine antagonist in the escape-avoidance response, but a tendency in the number of nonresponses was observed in the same direction as former results: male animals were more sensitive than females to the inhibitory effect of the low dose of haloperidol. It is concluded that the appearance of sex differences in the effects of haloperidol on active avoidance conditioning is a dose-dependent phenomenon.