Fig. 7. CV fusion and NSF binding are differentially sensitive to NEM. Exocytosis in isolated cortices was determined following incubation with various concentrations of NEM for 1 hour at room temperature. Sensitivity of exocytosis to 100 µM Ca²⁺ was then assessed (open bars). Mean±s.e.m. are shown, n=3. The binding of NSF was determined by incubating cortices with cytosol and 100 µM ATP--S. Prior to the binding assay, cytosol was treated for 1 hour at room temperature with the same concentrations of NEM used to inhibit CV exocytosis. NSF binding was determined by western blotting with anti-NSF antibody followed by densitometric scanning (filled bars).