Upregulation of the PDGF-alpha Receptor Precedes Asbestos-induced Lung Fibrosis in Rats

摘要

Platelet-derived growth factor-AA(PDGF-AA) and its matching alpha receptor (PDGF-Rα) are upregu- lated in rat lung fibroblasts(RLFs) after exposure to chrysotile asbestos fibers in vitro, which results in asbestos-induced RLF proliferation. We now report our in vivo observations, which show an increase in the expression of PDGF-Rα mPNA, but not PDGF-beta receptor mRNA, in asbestos-exposed rat lungs when compared with RNA from air-exposed(sham) and iron-exposed lungs. Western analysis of membrane preparations confirmed the observations on mRNA expression by demonstrating an in- crease in PDGF-Rα peptide expression in the asbestos-exposed rat lungs, compared with that in the air-exposed lungs.