FIGURE 2: Platelet activation and adhesion in GF and CONV-R Ldlr^−/− mice. Platelet activation is accompanied by the flipping and exposure of the procoagulant phosphatidylserine from the inner to the outer leaflet of the membrane. Compared to CONV-R counterparts, GF Ldlr^−/− mice show reduced phosphatidylserine exposure, yielding in a lower adhesion of platelets to subendothelial type III collagen and impaired thrombus formation. Abbreviations: PS, phosphatidylserine; EC, endothelial cell; VSMC, vascular smooth muscle cell.