Figure 1.
Actively cycling cells are present in the central and germinative zones of the mouse lens epithelium. (A) Paraffin section of the eye of an adult mouse that had received a single intraperitoneal injection of BrdU followed 24 hours later by an injection of 3H-TdR. BrdU-labeled or 3H-TdR-labeled nuclei were detected in the central (c) and germinative (g) zones of the lens epithelium. (B) A portion of the central (c) zone within the solid rectangle is shown at higher magnification; note the lens epithelial cells with BrdU-labeled (red nuclei) and 3H-TdR-labeled nuclei (arrowhead). (C) A portion of the germinative (g) zone within the dashed rectangle is shown at higher magnification. Cells with BrdU-labeled and 3H-TdR-labeled nuclei (arrowheads) are more prevalent in this region.