Fig. 5. Migration of the sling cells from the SVZ to the cortical midline. Individual litters were injected with BrdU at either E16 (A-F) or P3 (G-J) and then pups or whole litters were sacrificed at the times shown. Brains were sectioned coronally and processed for BrdU immunohistochemistry (red labeled cells in all panels) and counterstained with Sytox green (green cells in all panels except F). In F BrdU-labeled sections were double-labeled with PCNA which demonstrated the presence of proliferating cells within the sling (yellow cell in F). By using BrdU labeling sling cells could be seen migrating successively toward the midline (arrows in A-E and H and I). Scale bars: 200 µm in C for A-F and in J for G-J.