SEX-DIFFERENCES IN ESCAPE-AVOIDANCE RESPONSE IN MICE AFTER ACUTE ADMINISTRATION OF RACLOPRIDE, CLOZAPINE, AND SCH-23390

Sex differences in the effects of haloperidol in the escape-avoidance response in mice have previously been found in various studies carried out in our laboratory. Males were more affected than females by the d isruptive effects of this neuroleptic. The work described herein exten ded the study of these sex differences to raclopride, clozapine, and S CH 23390, using several doses of each drug in acute administration. Th e results showed dose-dependent sex differences in the deteriorating e ffects of these dopamine antagonists in the escape-avoidance response. Male mice were more affected by the inhibitory effects of these drugs , showing fewer escape responses and more nonresponses than females. S ex differences were found with all three of the dopamine antagonists s tudied, indicating, therefore, that these differences do not depend on a unique type of dopaminergic receptor. The results obtained in motor activity, measured by the number of crossings during the adaptation p eriod and the intertrial intervals, suggest that the motor effects are not the origin of these differences. It is concluded that, besides ha loperidol, other dopamine antagonists also show sex differences in the ir behavioral effects in escape-avoidance response in mice, with males being more affected than females by the inhibitory action of these dr ugs. (C) 1998 Elsevier Science Inc.