Fig. 5. No significant change in cell proliferation in the lens epithelium between wt and SPARC-null lenses, prior to mature cataract formation, was observed. (A) Pregnant mice were injected with 12.5 mg BrdU for 1 hour before sacrifice of the embryos. (B) Postnatal mice were injected with 2.5 mg BrdU for 2 hours before sacrifice. (C) Mice weighing in excess of 20 g received BrdU by minipump delivery (2 µg/g body weight/hour for 1 week). Hatched bars, wt lenses; filled bars, SPARC-null lenses. BrdU-labeled cells (+) were counted in nine sections per animal. Three to six mice were analyzed for each time point. DNA synthesis in SPARC-null mice increased when the cataract was mature and when inflammation was associated with rupture of the lens capsule (7.5 months and 1 year-old). D, day; M, month; Yr, year; LEC, lens epithelial cells. ^*, P<0.01.