Following many years when a great deal of attention was directed towards the intracellular roles of purines, there is expanding interest in the field of extracellular purinergic signalling. In this book we focus on the actions of purines in cardiovascular biology, where it is clear that they play major roles in both normal and pathophysiological conditions. Activation of different purinoceptor subtypes by purines can regulate cardiac contractility and electrical activity, modulate catecholamine-mediated responses both pre- and post-junctionally, trigger and mediate ischaemic preconditioning,...