Increased aggregate formation and PS exposure over a collagen surface under flow with transgenic platelets.
Inhibitory effect of U0126. Whole blood from WT or TG mice was perfused at a wall shear rate of 1000 seconds−1 for 4 minutes over a fibrillar collagen-coated surface. Blood from these 2 groups was assessed in the absence or presence of apyrase (0.1 U/mL) with or without saratin (10 μg/mL) and with or without U0126 (1 μM) for TG blood, as indicated. (A,C) Representative phase-contrast microscope images after perfusion. (B,D) Gray bars (░) represent the surface area coverage by platelets calculated from the phase-contrast images at the end of the perfusion period. White bars (■) represent the area coverage by platelets binding OG488-annexin V after perfusion (platelets exposing negatively charged PS) (n = 3-6) (*P < .001 vs WT;#P < .001 vs WT + apyrase;¶P < .001 vs TG + apyrase;♣P < 0.035 vs TG + apyrase).
