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

نویسندگان

  • D Z He
  • P Dallos
چکیده

The mammalian cochlea depends on an amplification process for its sensitivity and frequency-resolving capability. Outer hair cells are responsible for providing this amplification. It is usually assumed that the membrane-potential-driven somatic shape changes of these cells are the basis of the amplifying process. It is of interest to see whether mechanical reactance changes of the cells might accompany their changes in cell shape. We now show that the cylindrical outer hair cells change their axial stiffness as their membrane potential is altered. Cell stiffness was determined by optoelectronically measuring the amplitude of motion of a flexible vibrating fiber as it was loaded by the isolated cell. Voltage commands to the cell were delivered in a tight-seal whole-cell configuration. Cell stiffness was decreased by depolarization and increased by hyperpolarization.

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عنوان ژورنال:
  • Proceedings of the National Academy of Sciences of the United States of America

دوره 96 14  شماره 

صفحات  -

تاریخ انتشار 1999