Figure 2. Pathophysiology of the thrombotic response showing targets for antithrombotic drugs discussed in this chapter. 5HT, 5-hydroxytryptamine (serotonin); AA, arachidonic acid; ADP, adenosine diphosphate; ATP, adenosine triphosphate; Ca2+, calcium; COX1, cyclo-oxygenase 1; GP, glycoprotein; IXa, activated factor IX; P2X1, platelet ATP receptor; P2Y1/P2Y12, platelet ADP receptors; PAR, protease activated receptor; PLA2, phospholipase A2; PSGL1, P-selectin glycoprotein ligand 1; TF, tissue factor; TPα, thromboxane receptor α; TXA2, thromboxane A2; TXA2s, thromboxane A2 synthase; Va, activated factor V; VIIa, activated factor VII; VIIIa, activated factor VIII; VASP, vasodilator-stimulated phosphoprotein; vWF, von Willebrand factor; Xa, activated factor X; XIa, activated factor XI; XIIa, activated factor XII; XIIIa, activated factor XII. Modified from (22).