EFFECTS OF NEUROTROPHINS ON EARLY AUDITORY NEURONS IN CELL-CULTURE

DURING the first week of postnatal development, the innervation of the organ of Corti changes from an immature to an adult pattern. Dissocia ted cell cultures of early postnatal spiral ganglia were used to inves tigate the effects of nerve growth factor (NGF), brain derived neurotr ophic factor (BDNF) and neurotrophin-3 (NT-3) on maturing auditory neu rones. BDNF was the most potent stimulator of neuritogenesis, NT-3 pro vided the strongest support for neuronal survival, while NGF supported limited neuritogenesis, and only at pharmacological levels. These fin dings suggest that both BDNF and NT-3 participate in the postnatal mat uration of cochlear innervation and that NGF is most probably not invo lved in this process.