Figure 5. Type I and type II HC basolateral membranes show specific immunoreactivity to Kv1.8 antibody (magenta).
Antibodies for KV7.4 (A, green) and calretinin (B, cyan) were used as counterstains for calyx membrane (Kv7.4), type II HC cytoplasm (calretinin) and cytoplasm of striolar calyx-only afferents (calretinin). (A) Left, Cartoon showing KV7.4 on the calyx inner face membrane (CIF) and KV1.8 on the type I HC membrane. SC, supporting cell nuclei. A.1–3, Adult mouse utricle sections. KV7.4 antibody labeled calyces on two KV1.8-positive type I HCs (A.1), four KV1.8-positive type I HCs (A.2), and two KV1.8-negative type I HCs from a KV1.8−/− mouse (A.3). (B) Left, Cartoon showing cytoplasmic calretinin stain in calyx-only striolar afferents and most type II HCs, and KV1.8 on membranes of both HC types. In wildtype utricles, KV1.8 immunolocalized to basolateral membranes of type I and II HCs (B.1). KV1.8 immunolocalized to type I HCs in striola (B.2). Staining of supporting cell (SC) membranes by Kv1.8 antibody was non-specific, as it was present in KV1.8−/− tissue (B.3, B.4).