Figure 3. Pretreatment of intravitreal bevacizumab (IVB) remarkably reduced the levels of hypoxia inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF) in eyes with proliferative diabetic retinopathy (PDR). Immunohistochemistry for HIF-1α (A, C) and VEGF (B, D) was performed in the neovascular membranes (NVMs) of no IVB pretreated sham group (A, B) and IVB pretreated group (C, D). The stain of both HIF-1α and VEGF in the IVB pretreated group (C, D) was significantly lower than that of the no IVB pretreated sham group (A, B). Figures were selected as representative data from three independent experiments. Scale bars: 200 μm.