Fig. 1. Several platelet membrane receptors bind with extracellular factors in response to platelet activation by different situations, resulting in platelet adhesion and aggregation. GPIb in the platelet membrane binds von Willebrand factor (vWF) and mediates adhesion. Not illustrated is a second site on von Willebrand factor that binds to GPIIb-IIIa. GPIIB-IIIa in the membrane binds fibrinogen and mediates platelet-platelet interactions. ADP and thrombin receptors are illustrated to show the relationship between ADP stimulation and arachidonic acid pathway (AA), with release of thromboxane A2 (TXA2), which further stimulates aggregation. Reprinted with permission from Besa et al. (7).
