Platelet activation pathways and sites targeted by current and novel antiplatelet agents. Platelet activation pathways and sites targeted by current and novel antiplatelet agents. Arachidonic acid; ADP, adenosine diphosphate; c, cyclic; Ca2+, calcium; AMP, adenosinemonophosphate; COX-1, cyclo-oxygenase-1; DAG, diacylglycerol; GMP, guanosine monophosphate; GP, glycoprotein; IP3: inositol trisphosphate; PAR, protease activated receptor; PDE, phosphodiesterase; PI3K,phosphatidylinositol 3-kinase; PIP2: phosphatidylinositol 4,5-bisphosphate; PLC, phospholipase C; TP, thromboxane receptor; TRPC, transient receptor potential channel; TXA2, thromboxane A2; vWF, von Willebrand factor. Simon John Wilson et al. Heart 2017;103:573-580 Copyright © BMJ Publishing Group Ltd & British Cardiovascular Society. All rights reserved.