Substantia Nigra D1 Receptors and Stimulation of Striatal Cholinergic Interneurons by Dopamine: A Proposed Circuit Mechanism

摘要: Dopamine release can regulate striatal acetylcholine efflux in vivo through at least two receptor mechanisms: (1) direct inhibition by dopamine D2 receptors on the cholinergic neurons, and (2) excitation initiated D1 receptors. The neuroanatomical locus of latter population pathway(s) involved expression their influence are controversial issues. We have tested hypothesis that substantia nigra pars reticulata excitatory component dopaminergic actions output. In microdialysis was used awake rats. Infusion selective agonist R(+)-1-Phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine-7,8-diol (SKF 38393) hydrochloride into elicited a significant increase efflux. Likewise, D-amphetamine applied reverse dialysis produced an elevation output measured second probe striatum. Application striatum decrease could be reversed subsequently local application reticulata. A 2 mg/kg intraperitoneal dose D-amphetamine, which has no net effect under control conditions, when antagonist R(+)-7-Chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4, 5-tetrahydro-1H-3-benzazepine (SCH 23390) simultaneously via Thus, D1-mediated is reticulata, this contributes to effects indirect agonists such as These results indicate important role somatodendritic release, addition nerve terminal regulation activity basal ganglia circuits.