We began this project from a target gene GABRP, identified from DNA microarray. We firstly examined the expression patterns of GABRP in various culture conditions by using real-time PCR, western blot and immunostaining. Then we isolated lung tissue or type II cells from fetal, neonate, and adult rats, as well as hyperoxia-exposed rats. By using real-time PCR, we demonstrated the differential expression of all the ionotropic GABA receptor subunits during fetal lung development and after hyperoxia exposure. We further performed the functional study on fresh or cultured type II cells and rats, by using real-time PCR, western blot, immunostaining, biotinylation, immunproecipitation, isotope, RNA intereference, and lung fluid clearance assays. (1)The GABRP expression was regulated by culture conditions and closely associated with the type II cell-phenotype. (2)Among 19 known GABA receptor subunits, 17 were expressed in rat lungs and type II cells throughout the fetal and adult stages. Those subunits were dVeterinary Pathobiolog
