Platelet functional responses and signalling: the molecular relationship. Part 1: responses.

Blood platelets are small anucleated cells whose main function is to form a plug upon vascular damage to stop bleeding. This role involves a number of functional responses induced by different agonists and coordinated by an intricate network of signal transduction pathways. Understanding this network is vital from both basic research point of view and for the purposes of drug target identification in thrombosis and hemostasis. This review series will focus on the regulation of platelet signalling, on tracking the molecular relationship between receptor activation and functional responses, and on the networking aspects of these pathways. The present paper, first one out of two, focuses on the description of platelet functional responses and of the conditions for their triggering.