OB-FIG-61

24 hr survival after a ³H-thymidine injection on E16 (anterior coronal)

Figure 61.  An anterior coronal slice through the MOB that grazes the parenchyma of the growing olfactory bulb in an E17 embryo killed 24 hrs after a single exposure to ³H-thymidine on E16.  Unlabeled cells are the AOB output neurons, the MOB mitral cells and tufted cells generated before the morning of E16.  The few labeled cells outside the olfactory bulb SVZ are probably glial cells.  The olfactory and presumptive vomeronasal nerve bundles are full of labeled glial cells that proliferate outside the central nervous system.  The heavy label uptake in the olfactory epithelium and Jacobson’s organ indicate active proliferation.  The olfactory nerve blends with the ventral brain surface in the contact zone, obliterating the pial membrane.