Cholesterol suppresses KCNB1 oxidation-induced apoptosis.
A, percentage of N2A cells expressing wild-type KCNB1, positive to annexin V in the absence/presence of 30 μg/ml cholesterol ± 1 mm MβCD-cholesterol complex. Cells were preincubated for 2 h in DMEM containing cholesterol ± MβCD-cholesterol complex. n = 9 experiments. B, as in A in cells transfected with C73A. n = 5 experiments. C, percentage of N2A cells expressing wild-type KCNB1 positive to annexin V in the absence/presence of 3.0 mm MβCD. Cells were preincubated for 2 h in DMEM supplemented with MβCD. n = 6 experiments. D, as in C for N2A cells transfected with C73A. n = 4 experiments. In all experiments, cells were oxidized by 5-min exposure to 25 μm dTDP. Annexin V staining was performed 6 h post-oxidation. *, p < 0.05; **, p < 0.01.