English: Adhesion of Vwf −/− platelets. Mouse platelets were perfused at a shear rate of 1800 s−1 for 35 min on VWF-coated coverslips and adherent platelets were visualized on the VWF surface. Digital images were recorded at 0.25 image/s using “Replay” and “Histolab” software. For visualization, “Archimed” software (Microvision Instruments) was used to grab frames and record at a velocity of 10 images/s (40-fold acceleration). The set-up allows analyzing the changes of platelet morphology during their crossing of one field (an event that may extend up to 10 min). The release of a small discoid platelet from a proplatelet can be visualized in real-time: in the lower third of the image on the left, entering the field at 16′54″ is a dumbbell-shaped proplatelet (arrowhead) with a thin extension at its rear; the proplatelet translocates along the field and its extension corresponds to a small platelet (arrow at 18′06″), which is released at 20′42″ (arrow) from the original proplatelet (arrowhead). Bar is 20 µm.