Fig. 4. DiD-labelled GFP neurons with migrating cell morphology rostral, caudal, medial and lateral to injection site. (A) Schematic of an embryonic mouse brain illustrating DiD injection into the parietal cortex. Injection was performed at E15.5. (B) Transmitted-light image of a sagittal slice from a DiD-injected GAD67-GFP brain one and a half days after injection. (B9) Fluorescent micrograph showing the distribution of DiD-labelled GFP neurons in the boxed area in B. DiD labelling (magenta) was confined to the cerebral cortical wall. Merged view of GFP and DiD fluorescence. Insets show higher magnification views of the DiD-labelled GFP neurons indicated by straight lines. (C,D) Fluorescent micrographs showing DiD-labelled neurons in coronal sections one and a half days after injection. Insets show higher magnification views of the DiD-labelled GFP neurons indicated by straight lines. Both show the morphology of migrating neurons extending leading processes. Ctx, cortex; GE, ganglionic eminence; Hip, hippocampus; R, rostral; M, medial; V, ventral. Dotted lines indicate the slice outline. Scale bars: B, 500 µm; B', 300 µm; C, 100 µm; D, 200 µm; B9,C,D, insets, 10 µm.