Figure 1. Representative western blot bands for α-smooth muscle actin. A: Dose-response effects: fibroblasts were exposed to various concentrations of transforming growth factor (TGF)-β1 for 72 h. B: Time-response effects: fibroblasts were incubated with or without 10 ng/ml of TGF-β1 for up to 6 days. β-actin was used as an internal control. Densitimetric data represent the mean±SD of results from three independent experiments.