Activation of apo-nNOS with BMC. Full activation of apo-nNOS by ATPFT, partial activation by BMC, and no activation by GSH. Purified apo-nNOS was incubated for 1 h at 30 °C with various concentrations of the ATPFT fraction (closed circles) or BMC (open circles), or GSH (closed squares), and nNOS activity was assayed. BMC is maximally effective in the presence of glutathione (1 mM GSH; 0.2 mM GSSG) (36), and in the curve defined by open circles, glutathione was present at these concentrations in all samples. The effect of different concentrations of reduced GSH is also shown in the curve defined by closed squares.