YM-244769 is a potent, selective and orally active Na +/Ca 2+ exchanger (NCX) inhibitor. YM-244769 preferentially inhibits NCX3 and suppresses the unidirectional outward NCX current (Ca 2+ entry mode), with IC50s of 18 nM and 50 nM, respectively. YM-244769 efficiently protects against hypoxia/reoxygenation-induced SH-SY5Y neuronal cell damage. YM-244769 can also increase urine volume and urinary excretion of electrolytes in mice.