Fig. 4. Cell elongation in lens epithelial explants. (A) Diagram showing steps in the preparation of an epithelial explant [modified from Piatigorsky et al. (Piatigorsky et al., 1976)]. (B) Section of a lens epithelial explant treated with FGF1 (50 ng/ml) for 5 hours. Epithelial cells treated in this manner elongated from approximately 11 µm to an average of 12.5 µm. (C) Section of an explant treated with 20% bovine vitreous humor for 5 hours. Epithelial cells treated with vitreous humor elongated to over 18 µm in length. Explants in B and C were labeled with phalloidin (red) to locate cell boundaries and with TOTO-1 (green) to stain nuclei and cytoplasmic RNA. Scale bars in B and C are 10 µm.