Figure 3.

Effect of tectorigenin on extracellular signal-regulated kinase (ERK) activity. (A) Cell lysates were electrophoresed and phospho-ERK1/2 and ERK2 were detected using specific antibodies. (B) After treatment with U0126, tectorigenin, and/or H₂O₂, catalase expression was detected using a specific antibody and (C) cell viability was determined by the MTT assay. *Significantly different from H₂O₂-treated cells (P < 0.05). **Significantly different from tectorigenin plus H₂O₂-treated cells (P < 0.05).