Dopamine in the Rodent Cortex: Physiologic Effects and Structural Correlates

摘要

Dopamine (DA) has been implicated in the cortical pathophysiology of several neurological disorders, including schizophrenia and Parkinson's Disease. Until recently, motor areas of the neocortex were thought to receive only sparse DA innervation. It is now known that the motor cortex of rodents and primates are densely innervated by DA but its detailed circuitry and role in motor cortex function remain unclear. Immunohistochemistry and in situ hybridization were used to determine the laminar distribution and morphology of neurons that contain the protein and mRNA for D1a, D2, and D5 receptors. Numerous pyramidal shaped neuronal somata in layers II-VI of rodent motor cortex, were immunoreactive for D1a, D2, and D5 receptors, and sparse non- pyramidal shaped neurons in layers V-V were immunoreactive for the D1a receptor. Quantitative analysis revealed that all three receptor subtypes were expressed by neurons with distinct aminar distributions.