FIGURE 7.

Secretion from dense granules, α-granules, and lysosomes was assessed in RhoG^−/− platelets following stimulation with CRP or thrombin. A, dense granule secretion, measured by luminescence during aggregometry, was significantly reduced when CRP was the agonist but not when thrombin was used to induce aggregation. B, this pattern was repeated with α-granule secretion as measured by cell surface P-selectin (CD62P) expression. CRP stimulations for P-selectin expression were performed in the presence of 2 mm CaCl₂. Lysosomal secretion was measured using a plate-based β-hexosaminidase assay, and values are expressed as a percentage of the total β-hexosaminidase activity. C, lysosomal secretion in response to CRP stimulation (in the presence of 2 mm CaCl₂) was significantly reduced in RhoG^−/− platelets but was normal in response to thrombin stimulation. Data are presented as means ± S.E. from at least four mice/group.