Figure 2  Potential, K+ concentrations and pigmentation of stria vascularis in Slc26a4+/+ and Slc26a4-/- mice. a: Endocochlear potential and K+ concentrations in endolymph and perilymph at the apex (A) and base (B) of the cochlea. Numbers adjacent to symbols denote number of measurements. b-d: Pigmentation of stria vascularis in Slc26a4+/+ and Slc26a4-/- mice. b: View of stria vascularis through the bony capsule of the cochlea. OW, oval window, RW, round window; arrows, stria vascularis. c-d: Whole-mounts of stria vascularis isolated from age-matched mice. c: Laser-scanning images, bar = 10 μm, d: Quantification of pigmentation based on optical density.