Fig. 5

Cx26 expression in the cochlea of P30 Dfnb1^em274 HOM mice. Representative micrographs of cochlear paraffin sections stained with hematoxylin–eosin or immunostained against connexin-26 in WT (A-D) and Dfnb1^em274 HOM mice (E–H). WT mice show normal cochlear cytoarchitecture (A) and connexin 26 expression (B) in the spiral limbus (C), organ of Corti (supporting cells, arrows in C) and lateral wall (D), both in basal (A-D) and apical (not shown) regions. In contrast, Dfnb1.^em274 HOM mice present gross morphological alterations such as collapse of the tunnel of Corti (insets in E and G, asterisk in G) and a drastic reduction in connexin-26 expression, which is detected residually in just a few pillar cells (arrow in F) and supporting cells (arrows in H). These changes were most severe in the basal turn (E–F) compared to apical turn (G-H). LW, lateral wall; PC, pillar cells; SG, spiral ganglion; SL, spiral limbus; sTV, stria vascularis; TC, tunnel of Corti; TM, tectorial membrane. Scale bar: 100 μm (A-B) and 50 μm (C-H)