Aim: To investigate the effects of TGFbeta1 on the transcriptive activity of SP1, AP1 and Smad3-Smad4 in rat lung fibroblasts(RLF).
Methods: RLFs were isolated and cultured and then treated with 10 microg/L TGFbeta1. The transcriptive activity of SP1, AP1 and Smad3-Smad4 and the expression of plasminogen activator inhibitor I(PAI-1) and collagen I were detected by means of electrophoretic mobility shift assay (EMSA), Western blot and immunohistochemical staining.
Results: After treatment with 10 microg/L TGFbeta1, AP1, SP1 and Smad3-Smad4 were activated and the expression of collagen I and PAI-1 were increased.
Conclusion: TGFbeta1 may activate SP1, AP1 and Smad3-Smad4 and thus increase the expression of PAI-1 and collagen I.