Endothelial cell growth factor and ionophore A23187 stimulation of production of inositol phosphates in porcine aorta endothelial cells.

The existence of a bovine brain-derived endothelial cell growth factor has recently been reported, but its mode of action is unknown. We show that the endothelial cell growth factor is a potent stimulant of inositol monophosphate release in porcine aorta endothelial cells. Although the activation of phospholipase C by this factor does not appear to be dependent on Ca2+, the Ca2+ ionophore A23187 stimulates release of inositol phosphates. It is suggested that the inositol 1,4,5-trisphosphate 3-kinase/5-phosphomonoesterase pathway could account for the ionophore-induced changes in inositol 1,3,4-triphosphate.