Figure 3 Metabolism pathway of antiplatelet agents Figure 3 | Metabolism pathway of antiplatelet agents. P2Y12 receptors are a family of purinergic G-protein-coupled receptors and are activated by extracellular nucleotides, such as ADP. Platelets express at least two ADP receptors, P2Y1 and P2Y12, which couple to Gq and Gi proteins, respectively. Clopidogrel, prasugrel, ticagrelor, and cangrelor bind to the P2Y12 receptor and ultimately inhibit platelet activation and aggregation processes by modulating intraplatelet levels of cAMP and phosphorylated vasodilator-stimulated phosphoprotein (VASP-P). CYP, cytochrome P450; PKA, cAMP-dependent protein kinase; VASP, vasodilator-stimulated phosphoprotein. Reprinted with permission from Rollini, F. et al. Switching P2Y12-receptor inhibitors in patients with coronary artery disease. Nat. Rev. Cardiol. 13, 11–27 (2016), with permission from Macmillan Publishers Ltd. Reprinted with permission from Rollini, F. et al. Switching P2Y12-receptor inhibitors in patients with coronary artery disease. Nat. Rev. Cardiol. 13, 11–27 (2016), with permission from Macmillan Publishers Ltd. Miyazaki, Y. et al. (2017) Single or dual antiplatelet therapy after PCI Nat. Rev. Cardiol. doi:10.1038/nrcardio.2017.12