Early postembryonic neural development in the zebrafish: A 3-D reconstruction of forebrain proliferation zones shows their relation to prosomeres

Based on a section-by-section analysis of the morphology (combined silver/N issl stain) and of the distribution of proliferation zones (immunohistochem ical detection of the proliferating cell nuclear antigen) in the zebrafish (Danio rerio) forebrain at 5 days postfertilization, we created a three-dim ensional reconstruction of proliferation zones of that developmental stage. The resulting model visualizes the size, number, location and morphology o f forebrain proliferation zones. The latter foreshadow closely adult neuroa natomical forebrain entities. Furthermore, the detailed distribution of pro liferation zones in the posterior forebrain - but not in the more anterior secondary prosencephalon - supports a segmental prosomeric organization.