Figure 4-2 The NO scavenger PTIO at

Figure 4-2 The NO scavenger PTIO attenuated the inhibition of cell viability caused bySNPor silibinin treatment The MTT assay was used to determine the cell viability. A: The cells were treated with PTIO (50µM) fbr 1 h and cultured with various concentrations of SNP (100, 200, 300 or 400 µM) for 12 h. B: The cells were treated with PTIO (50 µM) for 1 h and cultured with various concentrations of silibinin (25, 50, 75 or 100 µM) for 12 h. C: The cells were treated with various concentrations of PTIO (25 or 50 µM) fbr 1 h and cultured with 50 gM silibinin for 12 h. The level of ROS was determined by DCF-DA staining and measured by flow cytometry. D: The expression levels of proteins involved in the ROS response were analysed by Western blotting. The cells were incubated with PTIO (50 µM) for 1 h and cultured with 50 µM silibinin for 12 h