Figure 3
Cochlea histology. (A) Gross morphology of the vestibular aqueduct and endolymphatic sac. The vestibular aqueduct and endolymphatic sac were enlarged in Slc26a4919-2A>G/919-2A>G mice. The length of the green lines represents the width of vestibular aqueduct. The red dash lines denote the contour of the sac. (B) Histology of the cochlea harvested from 3-month-old mice. On histological examination, the scala media was dilated in Slc26a4919-2A>G/919-2A>G mice, but not in Slc26a4T721M/T721M and Slc26a4919-2A>G/T721M mice (RM, Reissner's membrane; SV, stria vascularis; bar = 150 μm). (C) In the view of the organ of Corti panel, degeneration of hair cells was observed in Slc26a4919-2A>G/919-2A>G mice, but not in the other three groups of mice (IHC, inner hair cells; OHC 1–3, three rows of outer hair cells; bar = 150 μm). (D) Histology of the cochlear hair cells harvested from 3-month-old mice. Myosin VIIA expression was normal in Slc26a4T721M/T721M and Slc26a4919-2A>G/T721M mice, but was diminished in Slc26a4919-2A>G/919-2A>G mice (red: Myosin VIIA, blue: DAPI; bar = 50 μm). (E) Quantitative analysis of endolymphatic space. The cross-sectional area of the scala media (middle turn) in Slc26a4919-2A>G/919-2A>G mice was significantly larger than that in the other three groups. (F) The histology and expression of pendrin in the stria vascularis. Significant atrophy of stria vascularis and poor protein expression of pendrin were observed in Slc26a4919-2A>G/919-2A>G mice. In contrast, pendrin was normally distributed in the spiral prominence (SP) and root cells (RC) in Slc26a4CT721M/T721M and Slc26a4919-2A>G/T721M mice, similar to that in wild-type mice. Tissues were harvested from 3-month-old mice (green: pendrin, white dash line: the contour of stria vascularis; bar = 50 μm).
