IMMUNOCHEMICAL EVIDENCE FOR A FIBROBLAST GROWTH-FACTOR RECEPTOR IN ADULT RETINAL OPTIC FIBER AND SYNAPTIC LAYERS

Evidence for fibroblast growth factor receptors in the central nervous system has only been obtained using autoradiographic localization of fibroblast growth factor binding sites and messenger RNA. To clarify those neuronal functions that are regulated by fibroblast growth factor receptors, we have localized immunocytochemically the fibroblast growth factor receptor protein in bovine retina, a neural tissue of well-defined structure and function. The extracellular domain of the gene product referred to as fibroblast growth factor receptor 2 was expressed genetically in bacteria to obtain a polyclonal antibody. Positive staining was confined almost exclusively to the synaptic and optic fiber layers. Such a specific association suggests a role for this receptor in modulation of synaptic terminals and ganglion cell axons of the optic nerve, especially with respect to glutamate release.