Figure 9.

L-type VGCCs play a dual role on ACh release at the earlier stages of development. a, Summary plots showing that 10 μm Bay-K significantly increased m after blocking BK channels with 100 nm IbTx only in P4 and P6–P7 IHCs. Values from each individual cell are shown as black circles. b, Summary plots illustrating that 3 μm Nife did not further increase m after preincubating the cochlear preparations with 100 nm IbTx at P6–P7, as previously observed at P9–P11. c, Summary plot showing that 10 μm Bay-K was still able to increase m after blocking P/Q-, R-, and N-type VGCCs and BK channels with a toxin mixture containing 200 nm ω-Aga, 500 nm ω-CgTx, 500 nm SNX, and 100 nm IbTx. Data from P9–P11 mice are shown for comparison and were taken from Zorrilla de San Martín et al. (2010). Error bars indicate SEM. *p < 0.05, **p < 0.01, ***p < 0.001.