Fig. 2.

Auditory phenotypic characterization of Slc26a4^loop is common to all known Slc26a4 mouse models. A: A representative image of Slc26a4^loop mice shows the typical unsteady gait of the mutant mice that was determined by a panel of vestibular behavioral tests. B: Paint-filled inner ears of Slc26a4^loop P0 mice show a bulged fluid filled compartment, with a prominent volume increase in the cochlea and the vestibular system. C: Auditory brainstem response (ABR) test on 8-week old mice reveals that Slc26a4^loop mutants are profoundly deaf at three frequencies that were tested, 8Khz, 16Khz and 32Khz. An ABR recording for 8Khz is shown (red). D: Cross sections through the cochlea of Slc26a4^loop mice reveals hydrops of the endolymphatic spaces of the scala media (sm), whereas the perilymphatic spaces of the scala vestibuli (sv) and scala tympani (st) are smaller. E: Histogram graphic representation shows the quantified area of the different cochlear compartments as compared between normal and mutant mice. A prominent enlargement of the endolymph field scala media is apparent in Slc26a4^loop mice, at the expense of the smaller scala vestibuli and scala tympani. Scale bars equal 500 μm in panel B and D. Adapted from [42] with permission.