The effect of IGF-1 on 2-MeSADP–induced platelet aggregation. (A) Aspirin-treated, washed human platelets were stimulated with different concentrations of 2-MeSADP, IGF-1, or the combination of both agonists as noted, and platelet aggregation was measured as described in “Platelet aggregation.” All aggregations tracings were performed in the presence of 1 mg/mL fibrinogen. (B) Platelets were preincubated at 37°C for 10 minutes with 100 μM AG 1024 prior to the stimulation of the platelets. Platelets were stimulated with 30 nM 2-MeSADP or a combination of 30 nM 2-MeSADP and 100 nM IGF-1, as noted. All aggregation tracings are representative of at least 3 experiments from different donors.