Dose-dependent inhibition of human ADP-induced platelet aggregation by S-nitroso-AR545C. Human PRP (2.5 × 10⁸/mL) were incubated with increasing concentrations of S-nitroso-AR545C (•), AR545C (▪), or SNO-Glu (▴), and aggregation was induced with 5 μmol/L ADP. (▵), Aggregations obtained after addition of methylene blue (final concentration, 5 μmol/L) to the mixture of PRP and S-nitroso-AR545C.