Daily versus intermittent haloperidol administration: effects on catalepsy of mice

Résumé 0

"Drug effects on behaviour are closely related to the temporal patterns of their administration.Numerous studies have demonstrated that regular (daily) versus intermittent dosingof any drug can determine whether tolerance or sensitization is developed. The aim ofthis study was to examine if daily (10 days) or intermittent (every other day and every twodays) administration of haloperidol (0.75 mg/kg, ip) could affect differentially to catalepsyof male (experiment 1) and female mice (experiment 2). Catalepsy was measured by meansof the `bar test´, being evaluated 120 minutes after the last administration of haloperidol orsaline. In both experiments, as compared with controls, catalepsy increased significantly inmice treated with a single injection of haloperidol, as well as in the groups treated with haloperidolintermittently, although a marked tolerance to haloperidol-induced catalepsy afterdaily administration of the drug was observed. However, only the group of female mice treatedwith haloperidol every two days showed significantly more catalepsy than those treateddaily or every other day, suggesting that the effect of several schedules of drug administrationcan affect differentially to male and female mice."