Genes expressed in Flk-1-positive endothelial precursors are transiently up-regulated during angiogenesis in vivo. Time-course analysis of transcripts in hormonally induced ovaries. Vertical bars indicate the fold induction of each transcript as indicated from RNA collected from untreated (1) or hormonally induced ovaries during the follicular phase (FP) at 5 hours (2), 20 hours (3), and 44 hours (4) after pregnant mare's serum gonadotropin (PMS-G) stimulation and luteic phase (LP) at 8 hours (5), 16 hours (6), and 32 hours (7) after human chorionic gonadotropin (hCG) stimulation. Super ovulation in mice was induced as previously described,²¹  and the induction was quantified by real time RT-PCR and normalized on GAPDH expression. The data shown are the results of 3 independent experiments.