Cochlear outer hair cell motility.

  title={Cochlear outer hair cell motility.},
  author={Jonathan F Ashmore},
  journal={Physiological reviews},
  volume={88 1},
  • J. Ashmore
  • Published 2008
  • Biology
  • Physiological reviews
Normal hearing depends on sound amplification within the mammalian cochlea. The amplification, without which the auditory system is effectively deaf, can be traced to the correct functioning of a group of motile sensory hair cells, the outer hair cells of the cochlea. Acting like motor cells, outer hair cells produce forces that are driven by graded changes in membrane potential. The forces depend on the presence of a motor protein in the lateral membrane of the cells. This protein, known as… 

Figures from this paper

Cochlear amplification, outer hair cells and prestin

  • P. Dallos
  • Biology
    Current Opinion in Neurobiology
  • 2008

Prestin and Motility of the Cochlear Outer Hair Cell

This paper deals with the recent studies identifying the relationship between prestin and electromotility, the recent findings of the structure and function of prestin, and the recent prestin-related topics.

Outer Hair Cells and Electromotility.

  • J. Ashmore
  • Biology
    Cold Spring Harbor perspectives in medicine
  • 2018
Although the tertiary structure of prestin has yet to be determined, results from the presence of its homologs in nonmammalian species suggest a possible conformation in mammalian OHCs, how it can act like a transport protein, and how it may have evolved.

Cold Spring Harbour ‘Hearing and deafness’ Outer hair cells and electromotility Short title: Cochlear Outer Hair Cells

Results from the presence of its homologs in non-mammalian species suggest how prestin may be conformed, how it can act like a transport protein and how it may have evolved.

Cochlear hair cells: The sound‐sensing machines

Active outer hair cell motility can suppress vibrations in the organ of Corti

The results show that the interactions could be either constructive or destructive, which implies that the outer hair cells can either amplify or suppress vibrations in the organ of Corti, suggesting that the cochlear actuators can both amplify and suppress vibrations to enhance co chlear tuning.

Integrating the active process of hair cells with cochlear function

The auditory system is enhanced by an active process in cochlear hair cells that amplifies acoustic signals several hundred-fold, sharpens frequency selectivity and broadens the ear's dynamic range.

Effects of cochlear loading on the motility of active outer hair cells

The results suggest that somatic motility evolved to enhance a preexisting amplifier based on active hair-bundle motility, thus allowing mammals to hear high-frequency sounds.

The Spatial Pattern of Cochlear Amplification

Hair cell maturation is differentially regulated along the tonotopic axis of the mammalian cochlea

It is shown that the development of low‐ and high‐frequency hair cells is differentially regulated during pre‐hearing stages, with the former cells being more strongly dependent on experience‐independent Ca2+ action potential activity.



Prestin is the motor protein of cochlear outer hair cells

It is concluded that prestin is the motor protein of the cochlear outer hair cell, which is specifically expressed in outer hair cells that express prestin.

Molecular mechanisms of sound amplification in the mammalian cochlea.

It is shown here that outer hair cells selectively take up fructose, at rates high enough to suggest that a sugar transporter may be part of the motor complex.

Motility-associated hair-bundle motion in mammalian outer hair cells

The OHCs showed bundle movement with peak responses of up to 830 nm, which suggests that the bundle movement originated in somatic motility and that somatic Motility has a central role in cochlear amplification in mammals.

Motility of cochlear outer hair cells.

The mechanism underlying the shape changes induced by different stimuli are discussed, and the role of fast and slow motility in the physiology and pathology of auditory transduction is assessed.

Somatic stiffness of cochlear outer hair cells is voltage-dependent.

  • D. HeP. Dallos
  • Biology, Engineering
    Proceedings of the National Academy of Sciences of the United States of America
  • 1999
It is shown that the cylindrical outer hair cells change their axial stiffness as their membrane potential is altered and this change is accompanied by mechanical reactance changes of the cells.

Hair-Cell Mechanotransduction and Cochlear Amplification

Stereocilia displacement induced somatic motility of cochlear outer hair cells.

  • B. EvansP. Dallos
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 1993
It is shown here that mechanically induced hair-bundle deflection produces somatic motility of the cell, indicating that the cell may possess capabilities to affect its mechanical environment under control of its own receptor potential and, thereby, participate in a local cochlear feedback process.

Prestin is required for electromotility of the outer hair cell and for the cochlear amplifier

It is shown that targeted deletion of prestin in mice results in loss of outer hair cell electromotility in vitro and a 40–60 dB loss of cochlear sensitivity in vivo, without disruption of mechano-electrical transduction in outer hair cells.

Active hair bundle movements in auditory hair cells

Evidence for active hair bundle motion and its connection to MT channel adaptation is summarized and key factors for the hair bundle motor to play a role in the mammalian cochlea include the size and speed of force production.

The electrophysiology of hair cells.

This short review, with the main emphasis on hearing structures, will highlight some of the differences found between hair cells and describe the features that makes them effective transducers-their ability to convert mechanical stimuli into neural codes.