P2RX4 and atherosclerosis: Nevertheless, caution must be taken in attributing a deleterious role to the P2X4R in atherosclerosis development, because increased production of endothelial CXCL5 was protective against macrophage foam cell accumulation in atherosclerotic plaques by a mechanism that involves cholesterol efflux from macrophages in a rodent model of atherosclerosis [133].