Fig. 3.

Analysis of HIF-1α levels and angiogenic potentials. A, immunoblotting against HIF-1α revealed its relative elevation under Hx and the modest decline after Reox. Tubulin was used as loading control. B, collagen onplants, with or without CM, supported by two layers of nylon mesh were randomly placed on the CAM of 10-day-old chick embryos ex ovo. Induced angiogenesis was quantitated by taking random representative images of onplants and counting the number of branch points and extent of branching of blood vessels with the aid of a dissecting microscope in a blinded fashion. C, the angiogenic index is the percentage of branch points with newly formed blood vessels relative to controls. CM from both Hx and Reox induced a marked elevation in angiogenesis of 290 and 330%, respectively. 48N, 48-h normoxia; 48H, 48-h hypoxia; 48H-24R, 48-h hypoxia followed by 24-h normoxia; WB, Western blot; d, day.