The Effects of Basic Fibroblast Growth Factor on Cultured Glomerular Parietal Epithelial Cells

Ha, Tae Sun; Choi, Yong

Abstract

To elucidate the pathophysiology of crescentic glomerulonephritis, we investigated the effects of basic fibroblast growth factor(bFGF) on cultured rat parietal epithelial cells(PEC). Cultured cells were characterized as PEC by morphologic and immunohistochemical findings. PEC were cultured with or without various concentrations of bFGF, 1, 5, 25, and 50ng/ml for 0, 24, 48, and 96 hours. We found that bFGF is mitogenic to PEC in vitro at high concentrations and short-term incubation by direct cell counting and [3H]-thymidine incorporation assay. Also, cell viability evaluated by trypan-blue test increased at 5 and 25ng/ml of bFGF and decreased with time. We utilized the radionuclide-labeled precursors of extracellular matrix(ECM), glycosamine, leucine, and sulfate, for the assay of the utilization of those precursors by PEC. The utilization of [3H]-glycosamine showed the tendency of increase with exposed time at higher concentrations although it increased at concentration of 5ng/ml in 24 hours. The utilization of [3H]-leucine increased in 24 hours exposure time at concentration of 5ng/ml and in longer time at higher concentrations. Whereas, the utilization of [35S]-sulfate increased in 24 hours exposure time to bFGF at each concentration. Thus, bFGF may augment PEC proliferation and ECM production by cultured PEC and this could explain the role of bFGF in the pathophysiology of crescentic glomerulonephritis. The further experiments might be needed to elucidate the role of bFGF in molecular level.