Complex I inhibitor rotenone attenuates MPP+ induced ROS. N27 cells were treated with MPP+ or rotenone alone, or combined for 18 hours. H2O2 (ROS) levels were measured at that time using carboxy-H2-DCFDA and flow cytometry and are reported as % of MPP+ induced ROS. * represents p < 0.01 and # represents p < 0.05, both compared to the MPP+ treated cells. Data are from 3 independent experiments with n = 6 wells per experiment.