Exclusive labeling of dMSNs and iMSNs
(A–C) The presence of spines on the dendrites indicates that GFP-positive and RFP-positive cells are dMSNs and iMSNs, respectively. Arrows indicate the cell bodies. Scale bar, 30 μm.
(D–F) In the GPe, GFP-positive fibers were sparsely distributed, whereas RFP-positive fibers were dense. GFP-positive, but not RFP-positive, fibers extend caudally beyond the GPe, forming the direct pathway to the output nuclei of the basal ganglia. Scale bar, 100 μm.