Production of inositol phosphates in BALB/C 3T3 cells stimulated with basic fibroblast growth factor

When quiescent 3T3 fibroblast cells were pre-labelled with 3H]inositol and stimulated with basic fibroblast growth factor there was a stimulation of the hydrolysis of membrane lipids and the rapid production of 3H]inositol polyphosphates. Rapid and transient peaks of isomers of inositol phosphates with the chromatographic properties of inositol trisphosphates and inositol tetrakisphosphates were detectable by anion-exchange HPLC between 5 and 10 s after stimulation. These data suggest that upon stimulation the receptor for fibroblast growth factor is coupled to a phosphoinositidase C and that one of its signal-transducing pathways involves hydrolysis of inositol lipids and the production of inositol polyphosphates, some of which may act as intracellular signals mediating the cellular response. Chronic stimulation with basic fibroblast growth factor is associated with desensitization of the inositol lipid signaling pathway.