PDGF Gene Regulation by Vitamins A & D in Alveolization

The investigator proposes to assess the effect of RA, VitD, analogs, and dexamethasone individually or in combination on cell proliferation and expression of PDGFs and their receptors during lung development in vitro (Aim 1) and in vivo (Aim 2). This will include an evaluation of the effect of these treatments on alveolar formation and on lung function (Aim 2). Then, an analysis of the mechanisms regulating PDGF expression will be performed, aiming to characterize cis and trans elements potentially important on mediating transcriptional activation of the PDGF-A chain promoter during lung development (Aims 3 and 4).