Adenophostin A is a potent inositol trisphosphate (IP<sub>3</sub>) receptor agonist, but is much more potent than IP<sub>3</sub>.
IP<sub>3</sub>R is a ligand-gated intracellular Ca<sup>2+</sup> release channel that plays a central role in modulating cytoplasmic free Ca<sup>2+</sup> concentration (Ca<sup>2+</sup>i). Adenophostin A is structurally different from IP<sub>3</sub> but could elicit distinct calcium signals in cells.