CD36- and CD47-binding domains of TSP1 block NO-driven delay of platelet aggregation. Washed human platelets (2 × 10⁵ platelets/μL) were incubated in the presence of thrombin (0.2 U/mL) and exogenous NO (DEA/NO 10 μM) for 5 minutes in the presence of recombinant TSP1 constructs 3TSR and E123CaG-1 (2.2 nM) or NoC1 (2.2–22 nM) and aggregation was determined under high shear (A,B) or low shear (C) conditions. In other experiments, washed platelet were preincubated with the indicated concentrations of recombinant fragments and treated with DEA/NO (1 μM) for 60 seconds and lysed, and cGMP levels were determined by immunoassay (D). Data are representative of at least 3 experiments (A-C). Results are the mean (± SD) of at least 3 experiments (D).