3H-thymidine injection on E15, 2 hr survival
Figure 31 is a horizontal slice of an E15 embryo 2 hrs after its mother was injected with 3H‑thymidine. All NEP areas have uniformly thick accumulations of precursor cells at their superficial borders, except the tentatively identified olfactory bulb NEP that has clumps of heavily labeled nuclei interspersed with unlabeled nuclei. Perhaps the unlabeled cells are postmitotic neurons sequestered in the NEP before migration outwards. The peppering of labeled cells outside the NEP are in subventricular zones. There is a confluence between the basal telencephalic and olfactory SVZs. The most active and largest SVZ is outside the basal ganglionic NEP. A thick bundle of the olfactory/vomeronasal nerve contacts the anteromedial tip of the forebrain.