KB-R7943 is a potent, selective inhibitor of the reverse mode of the Na+/Ca2+ exchanger (IC50 = 0.7 M). KB-R7943 does not modify secondary pathology in the thalamus following focal cerebral stroke in rats. KB-R7943 blocks opening of the mitochondrial permeability transition pore. KB-R7943 restores endothelium-dependent relaxation induced by advanced glycosylation end products in rat aorta. KB-R7943 inhibits high glucose-induced endothelial ICAM-1 expression and monocyte-endothelial adhesion.