Figure 2

Systemic lipopolysaccharide (LPS) induced retinopathy of prematurity (ROP)-like changes in peripheral margins of retinal vasculature. A. On P7 retina in rats treated with LPS, the growth of peripheral retinal vessels was markedly delayed, and focal vascular tufts and abnormal angiogenesis developed (arrows). Scale bars = 200 μm. B. On P14 retina in the LPS-treated rats, the peripheral vascular margin in the superficial layer had abrupt vascular termination and tortuosity of surrounding vessels with a wide area of avascular retina (arrows) in contrast to controls. In the deep layer, a centrifugal growth of retinal vessels was markedly delayed (dashed line) compared to controls (arrows), and vascular density was also decreased. Scale bars = 200 μm. C. The ridge formation (arrows) and vascular tortuosity in the peripheral margin of vascularized retina are characteristic of retinopathy of prematurity in humans and similar to the findings of P14 retina in neonatal rats treated with systemic LPS (B).