Figure 4.

Intracellular signal transduction pathways involved in TR_1–41-induced platelet activation. After either (i) preincubation (22°C, 30 min) with 10 μM staurosporine, 100 nM or 1 μM wortmannin, or 100 μM genestein, or (ii) coincubation with buffer only (control), 10 μM PGI₂, or 10 μM the EDRF congener SNAC, diluted whole blood (or diluted platelet-rich plasma for the experiments with SNAC) were incubated (22°C, 10 min) with TR_1–41, TR_42–55, concomitant TR_1–41 and TR_42–55, or thrombin at the indicated concentrations and then fixed. The platelet surface binding of the P-selectin-specific mAb S12 was determined by whole-blood flow cytometry. Binding is expressed as a percent of the binding with maximal thrombin (2 units/ml) in normal volunteers. Data are mean ± SEM. n = 6.