The distance between echicetin molecules is critical for inducing platelet activation and aggregation.

<p>Washed human platelets were stimulated with EP under stirring conditions (1000 rpm). BSA coated polystyrene beads were used as negative control. Platelet aggregation stimulated by EP0.3 was considered as 100%. A. Representative aggregation curves of platelets stimulated with EP0.1, BSA-coated polystyrene beads, or echicetin-monomer are shown. B. Representative aggregation curves of platelets stimulated with EP0.3, EP0.2, EP0.1, EP0.05 or 5 times concentration of EP0.05 are shown. C. The graph shows the corresponding average values of aggregation from B. D. P-selectin surface expression on platelets was measured as Mean Fluorescence Intensity (MFI) using RPE-conjugated P-selectin antibody in flow cytometry. Thrombin (0.05 U/ml) and BSA-coated beads (BSA) were used as positive and negative controls, respectively. Results are mean±SD from 3 independent experiments. * p<0.05 versus EP0.3, and⁺p<0.05 versus EP0.1.