Figure 4.

Factor VIII vessel density ratio. Vessel density based on factor VIII staining was performed and quantitated as defined in Methods. (A) The ischemic limb vessel density was significantly greater than that in the nonischemic limb in the proximal and distal regions, suggesting that angiogenesis was occurring both proximally and distally in these groups. Due to extensive microscopic necrosis it was not possible to quantitate factor VIII density in the placebo animals and therefore to compare VEGF- and placebo-treated animals for this parameter. A minimum of three animals was used for group. (B) Representative picture of the massive microscopic necrosis observed in the ischemic hindlimb of the placebo group (Left). No microscopic necrosis was observed in the VEGF/VEGF–IRES (−) groups (Right).