This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Specific aims: (1) Compare effects of hypoxia and normoxia in fetal and newborn lung tissue as to HIFs, HIF-related gene expression, and vascular growth-related kinase activities, and to evaluate the in vitro effect of HIF prolyl hydroxylase domain-containing proteins PHD inhibition on these activities. (2) Examine the effect of PHD inhibition on HIF proteins, HIF-related gene products, and vascular growth-related kinase activities in vivo. (3) Evaluate the effect of PHD inhibition on pulmonary function, gas exchange, and vascular and alveolar development