Fig. 5.

CC atrophy is associated with decreased VEGFR2 phosphorylation in aged VEGF188/188 mice. (A) Choroidal vasculature of 18-month-old wt and VEGF188/188 mice was immunostained by cardiac perfusion of FITC-labeled Bandeiraea simplicifolia (BS-1) isolectin. In wt animals, flat-mounted choroids revealed a typical dense honeycomb vascular network. However, the choroidal vessels of VEGF188/188 animals appeared poorly branched and atrophied. The reduced vascular density was observed in both the central and the peripheral choroidal vasculature. (Scale bar, 200 μm.) (B) Quantification of the avascular area in the CC 15- to 16-month-old VEGF188/188 mice (n = 5) compared to aged-matched wt (n = 5) (P < 0.0001). (C) Level of VEGFR2 phosphorylation in choroid-RPE protein lysates of 16-month-old mice was quantified by Western blotting using [pY1214]-VEGFR2 specific antibody. The level of phosphorylated VEGFR2 was normalized for total VEGFR2. VEGF188/188 RPE-choroid complex displayed a significant reduction of the phosphorylation level of VEGFR2 compared to wt. (Scale bar, 100 μm.)