Effect of S-nitroso-AR545C or AR545C on rabbit platelet aggregation ex vivo. Female rabbits were injected with 0.5 mg/kg of S-nitroso-AR545C or 1 mg/kg AR545C intravenously (3 in each group). Blood samples were drawn before and at different time intervals after the injection. Platelet aggregation was induced ex vivo with 1 μg/mL botrocetin added to PRP prepared from animals treated with AR545C (▪) or S-nitroso-AR545C (•) and plotted relative to the pretreatment values. Results are expressed as mean ± SEM values for n = 3 animals in each group.