FIG. 4.

Neurotrophins promoted cochlear synaptogenesis. A De-afferented organs of Corti were co-cultured with SGNs. In one group of explants, NT-3 (10 ng/ml) and BDNF (10 ng/ml) were added to the culture. After 6 days, the explants were immunostained with antibodies to PSD-95, NF and CtBP2. Insets show enlarged views of synaptic zones in the yellow boxes. B After 6 days, addition of NTs significantly increased the percentage of IHCs innervated by SGNs in the co-cultured explant (Control, n = 8 explants; NTs, n = 11 explants). C After 6 days, addition of NTs significantly increased the average numbers of new synapses per IHC in the co-cultured explant (Control, n = 59 IHCs; NTs, n = 209 IHCs). *P < 0.05, Student’s t-test. Scale bar: 10 μm.