Duration of drug action of dopamine D2 agonists in mice with 6-hydroxydopamine-induced lesions.

Although 6-hydroxydopamine-induced (6-OHDA-induced) rats are a well-known Parkinson's disease model, the effects of dopamine D2 agonists in mice with 6-OHDA-induced lesions are not completely understood. We produced mice with 6-OHDA-induced lesions and measured their total locomotion counts following administration of several dopamine D2 agonists (pramipexole, ropinirole, cabergoline, rotigotine, apomorphine, talipexole, and quinelorane). Cabergoline showed the longest duration of drug action, which was in agreement with its long-lived anti-Parkinson effects in rats and humans. In contrast, pramipexole and ropinirole had notably short durations of drug action. We demonstrated that mice with 6-OHDA-induced lesions accompanied with significant lesions in the striatum may be reasonable models to predict the action duration of anti-Parkinson drug candidates in humans.