Pflügers Archiv

, Volume 447, Issue 3, pp 328–336

Active and passive behaviour in the regulation of stiffness of the lateral wall in outer hair cells of the guinea-pig

  • Tamás József Batta
  • György Panyi
  • Rezső Gáspár
  • István Sziklai
Sensory Systems

DOI: 10.1007/s00424-003-1186-9

Cite this article as:
Batta, T.J., Panyi, G., Gáspár, R. et al. Pflugers Arch - Eur J Physiol (2003) 447: 328. doi:10.1007/s00424-003-1186-9

Abstract

The stiffness of the outer hair cell (OHC) lateral wall, measured by the micropipette aspiration technique, is non-linear, decreasing from the ciliary pole (stiffness parameter Sp 1.83±0.13 nN/µm n=10) towards the cell base (Sp 1.14±0.16 nN/µm, n=10) irrespective of the cochleoapical or cochleobasal origin of the cells. The length of the aspirated lateral wall segment was related exponentially to the duration of the applied negative pressure (6 cm H2O) in the synaptic region of the OHCs whereas an active, sigmoid component was observed between 30 and 60 s in the supranuclear regions. A significant increase of the midlateral wall stiffness (to 1.91±0.23 nN/µm; n=10) was observed in calcium-free medium and the sigmoid component of the response of the lateral wall was abolished. Salicylate (5 mM) had no significant effect on the active sigmoid behaviour of the lateral wall (n=10). Gadolinium (5 mM), a non-specific cation channel blocker, increased the stiffness of the lateral wall and attenuated the active component (n=10). The motor protein prestin thus does not seem to be involved in the active stiffness regulation seen in this study. A role for the cortical cytoskeleton in the regulation of stiffness seems reasonable according to our model. The mechanism may involve calcium-dependent metabolic modification of cytoskeletal or membrane proteins.

Keywords

Glass micropipette aspiration technique Stiffness parameter Elastic unit Calcium 

Copyright information

© Springer-Verlag  2003

Authors and Affiliations

  • Tamás József Batta
    • 1
  • György Panyi
    • 2
  • Rezső Gáspár
    • 2
  • István Sziklai
    • 1
  1. 1.ORL Clinic, Medical and Health Science CentreUniversity of DebrecenDebrecenHungary
  2. 2.Department of Biophysics and Cell Biology, Research Centre for Molecular Medicine, Medical and Health Science CentreUniversity of DebrecenDebrecenHungary