Extracellular ATP attenuates ischemia-induced caspase-3 cleavage in human endothelial cells

► Ischemia-induced apoptosis is accompanied by ATP release from endothelial cells. ► Inhibition of ATP breakdown reduces ischemia-induced endothelial cell apoptosis. ► Protective effects of extracellular ATP seem to be mediated by P2Y-receptors. ► Reduction of ischemia-induced apoptosis is due to MEK/ERK- and PI3K/Akt-signaling.