Fig. 5

General cochlear morphology of brevican-deficient (bcan^−/−) mice. a, b Immunohistochemical verification of the presence of brevican (BCAN) in wildtype (bcan^+/+) mouse cochleae (a, green) and of its absence in bcan^−/− mouse cochleae (b, green). The ribbon synapses were labeled with the ribeye marker CtBP2 (a, b, red). Maximum intensity projections of confocal stacks of stretches of 5–6 IHCs of cochlear whole-mount preparations, scale 5 μm. c, d Hematoxylin-eosin staining of paraffin sections of bcan^+/+ (c) and bcan^−/− mouse cochleae (d) did not reveal any obvious differences in the general morphology of cochlear tissue. A higher magnification of the basilar membrane is depicted in the insets. Scale 100 μm, scale inset 25 μm. e Quantification of the number of ribbon synapses (CtBP2-positive punctae) per IHC in apical and midbasal cochlear turns did not yield any genotype-specific differences (apical, bcan^+/+: 11.8 ± 1.1, n = 5/38 whole-mounts/IHCs, bcan^−/−: 11.4 ± 0.9, n = 5/40, p = 0.524, t test; midbasal, bcan^+/+: 16.3 ± 0.7, n = 5/43, bcan^−/−: 16.1 ± 0.5, n = 5/41, p = 0.62, t test). Data are presented as mean ± S.D