FCF1 and central nervous system cancer: Fig. 2 shows whole-cell current recordings of BK in HEK 293 cells transfected with BKα (see Methods), before and after treatment with 5 mM MβCD. An increase in whole-cell current (2–5 fold) by depletion of membrane cholesterol is evident (Fig. 2C). This result differs from findings obtained for BK channels in glioma cells [25] but is consistent with previously published bilayer data [6], as well as data obtained in IGR 39 cells [45]. The time course of current rise is gradual, with maximal current observed at about 10 minutes after the application of MβCD (Fig. 2D).