Focal delivery of fibroblast growth factor-1 by transfected cells induces spiral ganglion neurite targeting in vitro

✍ Scribed by S. Dazert; D. Kim; L. Luo; C. Aletsee; S. Garfunkel; T. Maciag; A. Baird; A. F. Ryan

• Book ID: 101259616
• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 293 KB
• Volume: 177
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/(sici)1097-4652(199810)177:1<123::aid-jcp13>3.0.co;2-e

✦ Synopsis

Sensory cells in the cochlea of the rat transiently express acidic fibroblast growth factor (FGF-1) during the developmental period of terminal innervation in the sensory epithelium. To explore the potential role of FGF-1 in terminal innervation events, the response of cochlear ganglion neurons to FGF-1 was evaluated in culture. Explants from the spiral ganglion of postnatal day 5 rats were cultured in the presence of exogenous FGF-1, with or without heparin. FGF-1 in the culture medium produced a dose-dependent increase in the number and length of neurites produced by spiral ganglion neurons, a response that was enhanced by heparin. To assess the effects of FGF-1 produced by a focal, cellular source, additional explants were cocultured with 3T3 cell transfectants that secrete FGF-1. Neurites that came into contact with FGF-1 secreting cells branched, formed bouton-like terminal swellings on the surface of the transfectants, and stopped extending. The results suggest that FGF-1 may stimulate neurite extension into the sensory epithelium of the cochlea and that focal production of FGF-1 may contribute to the formation of contacts on sensory cells by developing neurites.