8-hydroxy-2-(di-n-propylamino)tetralin Reduces Striatal Glutamate in an Animal Model of Parkinson's Disease

Using in-vivo microdialysis, we examined the effect of the serotonin 5-HT1A agonist R-(+)-8-hydroxy-2-(di-n-propylamino)tetralin on striatal extracellular excitatory amino acids in an animal model of Parkinson's disease. Extracellular glutamate and aspartate in the dopamine-denervated striatum of unilateral 6-hydroxydopamine-lesioned rats were significantly decreased by acute subcutaneous injection of R-(+)-8-hydroxy-2-(di-n-propylamino) tetralin (0.3 mg/kg). Although not quantified in the present study, a concomitant increase in locomotor activity was anecdotally observed following R-(+)-8-hydroxy-2-(di-n-propylamino)tetralin. These results suggest that systemic administration of a 5-HT1A agonist can reduce glutamate neurotransmission in the dopamine-denervated striatum. The results are discussed with respect to the treatment of Parkinson's disease.