Fig. 1. Stria vascularis and claudin-11 in 10-week-old wild-type mice. (A) Toluidine-blue-stained Epon semi-thin sections of the wild-type cochlea. (left) Stria vascularis (arrowheads) are located on the lateral wall of the cochlear duct. Asterisk, scala media; arrow, the organ of Corti. (See also Fig. 7A.) (right) Stria vascularis is enlarged. Yellow and pink arrowheads represent the marginal and basal cell layers, respectively. (B) Schematic drawing of the cellular architecture of stria vascularis. Three compartments are represented: compartment I (I) is the scala media filled with endolymph; compartment II (II) is the intrastrial space delineated by marginal and basal cell layers; compartment III (III) is connective tissue of the spiral ligament connected to the perilymphatic space. Green cells in compartments II and III are called `intermediate cells' and `fibrocytes', respectively. (C) Double immunofluorescence microscopy of frozen sections of stria vascularis with anti-claudin-11 pAb and anti-occludin mAb (a) or anti-ZO-1 pAb and anti-E-cadherin mAb (b). Occludin is concentrated at TJs of both marginal (yellow arrowhead) and basal (pink arrowhead) cell layers, whereas claudin-11 is detected only in TJs of basal cell layers. In frozen sections, TJs of marginal cells appear as dots, but those of basal cells are observed as discontinuous short lines. ZO-1 and E-cadherin are concentrated at cell-cell borders of both layers but do not colocalize. Bars, 50 µm (A, left), 20 µm (A, right, C).