CANNABINOID EFFECTS IN BASAL GANGLIA IN A RAT MODEL OF PARKINSONS-DISEASE

Cannabinoid receptors in the brain are highly concentrated in the basa l ganglia, which is in accordance with their well known effects on mot or behavior. In this study, rats with 6-hydroxydopamine lesions of the nigrostriatal pathway were implanted with cannulae in the striatum, g lobus pallidus and substantia nigra. The effect of unilateral infusion of the potent cannabinoid agonist CP55,940 on turning behavior was st udied for each structure. Lesioned animals responded to intrapallidal and intrastriatal administration of the cannabinoid in a manner that w as similar to that of unlesioned animals. However, lesioned animals sh owed greater contralateral turning in response to the cannabinoid infu sions in the substantia nigra than unlesioned animals. (C) 1998 Publis hed by Elsevier Science Ireland Ltd. All rights reserved.