Figure 1.
Activation-independent and shear rate-dependent aggregation and disaggregation of platelets perfused over immobilized VWF. Whole blood containing 93 μM PPACK as the anticoagulant, 10 μM PG E1 to block platelet activation, and 10 μM mepacrine to render platelets fluorescent for visualization, was perfused over a surface coated with immobilized VWF. The images shown are single frames from a real-time recording (Video S1). A timeline (black horizontal bar) indicates at what moment during the perfusion experiment a given image was taken, as shown by the position of the corresponding letter (A, 55 seconds; B, 130 seconds; and C, 380 seconds).Avertical white bar separates the timeline in segments corresponding to periods of perfusion at different wall shear rates (5500 or 13 000 s-1). The images are representative of 3 separate experiments performed with blood from different donors.