Fig. 2. BK promotes eNOS redistribution into a Triton X-100-insoluble fraction. eNOS-GFP ECV 304 cells were incubated with BK (10 µM) or vehicle for 10 minutes then fractionated into cytosol and membrane fractions. Membrane fractions were further fractionated into 0.5% Triton X-100-soluble (TS) and -insoluble fractions (TIF). eNOS protein abundance was assessed in fractions by western blot analysis. While BK stimulation did not influence the distribution of eNOS in membrane (memb) and cytosolic (cytosol) fractions (left panel), BK stimulation was associated with an enrichment of eNOS within the TIF component of the membrane fraction (right panel). Control experiments demonstrate that caveolin protein levels (cav) are enriched in membrane fractions compared to cytosol, and TIF compared to TS (lower panel). Each panel is representative of three separate experiments.