FIGURE 6.

Rhinocetin inhibits calcium mobilization and granule secretion. Calcium mobilization was measured in Fluo4 NW dye loaded platelets by spectrofluorimetry in the presence or absence of 100 μg/ml rhinocetin. Platelets were activated with 1 μg/ml of collagen (A), and the percentage of inhibition was shown (B). Data represent mean ± S.D. (n = 3). Platelets were stimulated with 1 μg/ml of collagen in the presence and absence of different concentrations of rhinocetin, and the level of P-selectin exposure was measured by flow cytometry (C). Data represent mean ± S.D. (n = 3). The level of P-selectin exposure with vehicle was taken as 100%. R represents the amount of P-selectin exposure in resting platelets. The level of ATP release upon 1 μg/ml of collagen activation in the presence or absence of different concentrations of rhinocetin at 90 s was measured by luminescence aggregometer (D). The level of ATP release obtained with vehicle was taken as 100% (E). Data represent mean ± S.D. (n = 3). **, p < 0.01; ***, p < 0.001 as calculated by t test. AU, arbitrary units.