Charge displacement induced by rapid stretch in the basolateral membrane of the guinea-pig outer hair cell.
The properties of the basolateral membrane of cochlear outer hair cells were studied under whole-cell patch clamp to measure currents and capacitance changes associated with mechanical deformation. Stretching the membrane of outer hair cells along the cell axis generated a transient inward current, and subsequent relaxation of the membrane produced a similar transient outward current. These mechanically activated currents were velocity dependent with a mean sensitivity of 29 pA s mm-1. Unlike ionic currents, these currents did not reverse, but reached a peak magnitude at -33 mV. Stretching the cell also resulted in a measurable capacitance decrease of 0.3-1.1 pF microns-1. These results suggest that membrane stretch can induce a rapid charge movement resulting from the reversal of the electromechanical transduction process in outer hair cells.
Department of Physiology, School of Medical Sciences, University Walk, Bristol, U.K.
J E
JE
Gale
J F
JF
Ashmore
D000818:Animals; D002462:Cell Membrane / Q000502:physiology; D004553:Electric Conductivity / Q000502:physiology; D004558:Electric Stimulation / Q000379:methods; D004594:Electrophysiology / Q000379:methods; D006168:Guinea Pigs; D018072:Hair Cells, Auditory, Outer / Q000502:physiology*; D066298:In Vitro Techniques; D008433:Mathematics; D008564:Membrane Potentials / Q000502:physiology; D008959:Models, Neurological; D013314:Stress, Mechanical