Immunolocalization of voltage-gated potassium channel Kv3.1b subunit in the cochlea.

Immunohistochemical localization of voltage-gated potassium channel Kv3.1b subunit was studied in the cochlea. Intense Kv3.1b-like immunoreactivity was present in the type I, type III, type IV and suprastrial fibrocytes of the cochlear lateral wall. Immunostaining was also found in the interdental cells and the fibrocytes of the spiral limbus and in the supralimbal dark cells. K+ ions, which play a pivotal role in the mechanosensory transduction process in the inner ear, are recycled via gap junctional networks in the cochlea. These results suggest that the voltage-gated potassium channel, containing Kv3.1b, in the cochlear lateral wall fibrocytes may control the intracellular potential and play an important role in regulating the potassium ion recycling mechanism via gap junctions in the inner ear.