24 hr survival after a ³H-thymidine injection on E17 (anterior coronal)

Figure 76.  A coronal slice through the MOB anterior to the lumen of the olfactory recess of the lateral ventricle in an E18 embryo killed 24 hrs after a single exposure to ³H-thymidine on E17.  Labeled cells are present in the core (the SVZ of the olfactory bulb) and in the olfactory nerve layer.  Nearly all cells are unlabeled in the internal and external plexiform layers and the mitral cell layer—all generated before the morning of E17.  The few labeled cells are probably locally-multiplying glia.  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.