inositol 1,4,5-trisphosphate


in·o·si·tol 1,4,5-·tris·phos·phate (IP3),

a second messenger formed from phosphatidylinositol 4,5-bisphosphate; triggers the release of calcium ions from special vesicles of the endoplasmic reticulum; has a role in the activation of neutrophils.