2-Aminoethoxydiphenyl borate(2-APB)is a syntheticcompound that was originally introduced as amembrane-permeable inhibitor of intracellular inositol1,4,5trisphosphate receptors,and has been used extensively as a modulatorof manykinds of ion transport proteins.Studies revealed a complex mechanism of action for 2-APB and its analogs on ion channels.