Figure 4-4039.

Three-μm paraffin sections of inner retina from 18-day-old Sprague Dawley rats immunolabeled with caspase-3. A: Untreated sham rats. B: Sham rats treated with 100 mg/kg/day STI571. C: Untreated ROP. D: ROP rats treated with 100 mg/kg/day STI571. Original magnification, ×400. N = 6 to 8 rats per group. Caspase-3-positive cells (arrows) were confirmed to be pericytes by examination of α-smooth muscle cell immunolabeling in consecutive sections (not shown). Caspase-3-positive cells are associated with blood vessels (asterisks) and most numerous in ROP rats treated with 100 mg/kg/day STI571 (D). Sections are counterstained with eosin. GCL, ganglion cell layer. Quantitation of apoptotic pericytes is shown graphically. Values are means ± SEM. N = 6 to 8 rats per group. U, untreated. *, P < 0.0001 compared to all groups. **, P < 0.001 compared to sham groups.