Effects of baicalein (Bai) on rotenone (RT)-induced loss of ΔΨm. Cells were pretreated with Bai for 1 hour and then cotreated with 20 μM RT for 6 hours in serum-free medium. The ΔΨm was determined by the mean fluorescent intensity (MFI) of Rh123. (A) Representative fluorescent images. Scale bar: 50 μm. (B) Statistical analysis. At least 600 randomly selected cells were counted in each experiment (n = 3, #P < 0.01 versus control, *P < 0.01 versus RT treatment).