Acidic fibroblast growth factor inhibits junctional communication of Schwann cells in culture

Abstract

effect of acidic fibroblast growth factor (aFCF) was investigated on junctional communication of rat Schwann cells (SC) in culture. As measured by dye transfer, the incidence of coupling between SC was very low during the phase of proliferation and increased slowly and progressively with time under culture conditions that induced the myelinating phenotype. Treatment with aFCF alone or in combination with heparin decreased markedly coupling between SC in both culture stages. The coupling inhibition was rapid, the earliest effects being apparent 5-15 min after addition of grdwth factor, and was transient with a slower recovery of coupling at 1-3 h. The uncoupling effect of aFCF could be prevented by an inhibitor of protein-tyrosine kinase. Addition of heparin to cultures decreased the most effective aFCF concentration by 100-fold, from 100 ng ml-1 to 1 ng ml-1 The dose-response curves exhibited a characteristic windowshape. The results suggest that FGF might be involved in the regulation of the junctional communication between rat SC via tyrosine kinases. [Neurol Res 2000; 22: 685-691]