EBE down-regulated iNOS over-expression in PC12 cells stimulated by 6-OHDA. Cells were incubated with EBE (25, 50, 100 and 200 μg/ml) for 12 hours prior to a 6-hour 6-OHDA stimulation. (A) Western blot analysis showing 6-OHDA-induced iNOS over-expression was inhibited by pretreatment of different concentrations of EBE. (B) Densitometric analysis of iNOS expression with measurements of each blot expressed relative to that of the control. Three times independent experiments showed the same tendency of the iNOS expression.