Besipirdine (HP 749) reduces schedule-induced polydipsia in rats.

The aim of the present paper is to report on the adrenergic and serotonergic effects of besipirdine (HP 749) in vivo and to discuss its potential use in the treatment of obsessive compulsive disorder. Besipirdine inhibited biogenic amine uptake in vitro. It prevented tetrabenazine-induced ptosis in mice and potentiated the 5-hydroxytryptophan-induced serotonin syndrome in rats. Furthermore, it decreased schedule-induced polydipsic behavior in rats. Schedule-induced polydipsia may be a model for obsessive compulsive disorder. Previous results from our group have shown that certain selective serotonin reuptake inhibitors decrease schedule-induced polydipsia after 14-21 days of treatment. Besipirdine reduced schedule-induced polydipsic behavior immediately and this reduction lasted throughout the duration of the experiment (29 days).