Figure 4.

Reduction of PC number is not accompanied by BV length shrinkage following imatinib treatment. (a) Illustrated step-by-step method for BV length measurement: normalized grayscale image of albumin IHC labels merged from n = 5 optical slides (top); binary image (right top); the skeleton of BVs used to measure length (right bottom). (b) Comparison of blood vessel lengths in retinal layers in control (C), intravitreally injected (2 µL, 8 µg/µL imatinib, IV) and intraperitoneally injected (100 mg/kg/d, 2 days imatinib, IP) retinas. (c) Comparison of BV length/PC number ratios on the same dataset suggests that PCs fill out the gaps after PC loss and protect the underlying vasculature. Measurements on capillary diameters (d) show a reduction in the IL and DL (e). Measurements were made layer-by-layer in a 0.3*0.3 mm area from a mid-central region. C, IV, IP n = 4, 4, 3. Error bars are ± SD. * p < 0.05; ** p < 0.01.