NO Deficiency and HIF-1a6 Stabilization in HUVECs by Bonferroni’s multiple comparison test or Student’s t-tests, where applicable. anti HIF-1a (BD Transduction Laboratories, Franklin Lakes, NJ, USA) and anti b-actin (Sigma Chemicals, St. Louis, MO, USA). Reagents and antibodies All tissue culture reagents were from Sigma Chemicals (St. Louis, MO, USA). The following reagents were purchased as indicated: human VEGF165 from Calbiochem (Darmstadt, Germany); collagen type IV from BD Bioscience (Bedford, MA, USA); L-NAME, ODQ (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin- 1-one), DETA-NO (2,29 (hydroxynitrosohydrazono)bis-ethani- mine) from Sigma Chemicals (St. Louis, MO, USA). Antibodies used were: rabbit polyclonals anti caspase-3 (Cell Signalling, Beverly, MA, USA), anti Bax and anti KRD (Santa Cruz Biotechnology, Santa Cruz, CA, USA), and mouse monoclonals anti Bcl-2 (Santa Cruz Biotechnology), anti eNOS, References 1. 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