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Gap Junctions and Cochlear Homeostasis

  • H.-B. Zhao
  • T. Kikuchi
  • A. Ngezahayo
  • T. W. WhiteEmail author
Article

Abstract

Gap junctions play a critical role in hearing and mutations in connexin genes cause a high incidence of human deafness. Pathogenesis mainly occurs in the cochlea, where gap junctions form extensive networks between non-sensory cells that can be divided into two independent gap junction systems, the epithelial cell gap junction system and the connective tissue cell gap junction system. At least four different connexins have been reported to be present in the mammalian inner ear, and gap junctions are thought to provide a route for recycling potassium ions that pass through the sensory cells during the mechanosensory transduction process back to the endolymph. Here we review the cochlear gap junction networks and their hypothesized role in potassium ion recycling mechanism, pharmacological and physiological gating of cochlear connexins, animal models harboring connexin mutations and functional studies of mutant channels that cause human deafness. These studies elucidate gap junction functions in the cochlea and also provide insight for understanding the pathogenesis of this common hereditary deafness induced by connexin mutations.

Keywords

Cochlea Supporting cell Gap junction Connexin Potassium Deafness 

Notes

Acknowledgement

The authors gratefully acknowledge J.C. Adams (Harvard Medical School) and G. Meşe (SUNY Stony Brook) for their critical reading of this manuscript. Work in our laboratories is supported in part by NIH grants DC06652 (T.W.W.) and DC05989 (H.-B.Z.). We apologize to colleagues whose work could not be cited here due to space constraints.

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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • H.-B. Zhao
    • 1
  • T. Kikuchi
    • 2
  • A. Ngezahayo
    • 3
  • T. W. White
    • 4
    Email author
  1. 1.Department of Surgery-OtolaryngologyUniversity of Kentucky Medical CenterLexingtonUSA
  2. 2.Department of Otolaryngology-Head and Neck SurgeryTohoku University Graduate School of MedicineSendaiJapan
  3. 3.Institute of BiophysicsUniversity of HannoverHannoverGermany
  4. 4.Department of Physiology and BiophysicsState University of New YorkStony BrookUSA

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