Figure 2

Progression of BrdU labelled cells along the lateral ventricular choroid plexus during development. A. Coronal section for P5 Monodelphis pup after a single injection of BrdU. Positive nuclei were seen in choroid plexus epithelial cells at the root of the plexus (arrow). B. After a second injection (24 h later) two distinct labelled populations of nuclei were seen on the same side (dorsal) of the plexus (arrows). C. Three consecutive injections of BrdU 24 h apart show nuclei of choroid plexus epithelial cells being 'pushed' along the stalk of the plexus, away from the root, by newly dividing cells of the structure. Camera lucida images on the right depict the movement of the nuclei as the plexus increases in size. Scale bar: 50 μm for all. Abbreviations: bv, blood vessel; cp, choroid plexus; csf, cerebrospinal fluid; ne, neuroependyma.