Outer hair cell somatic, not hair bundle, motility is the basis of the cochlear amplifier.
Sensitivity, dynamic range and frequency tuning of the cochlea are attributed to amplification involving outer hair cell stereocilia and/or somatic motility. We measured acoustically and electrically elicited basilar membrane displacements from the cochleae of wild-type and Tecta(DeltaENT/DeltaENT) mice, in which stereocilia are unable to contribute to amplification near threshold. Electrically elicited responses from Tecta(DeltaENT/DeltaENT) mice were markedly similar to acoustically and electrically elicited responses from wild-type mice. We conclude that somatic, and not stereocilia, motility is the basis of cochlear amplification.
Mellado Lagarde
Marcia M
MM
School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9QG, UK.
Drexl
Markus
M
Lukashkina
Victoria A
VA
Lukashkin
Andrei N
AN
Russell
Ian J
IJ
D000161:Acoustic Stimulation / Q000379:methods; D000669:Amplifiers, Electronic; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D001309:Auditory Threshold / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D001489:Basilar Membrane / Q000502:physiology*; D002465:Cell Movement / Q000502:physiology*; D003051:Cochlea / Q000166:cytology*; D004307:Dose-Response Relationship, Radiation; D004558:Electric Stimulation / Q000379:methods; D016326:Extracellular Matrix Proteins / Q000235:genetics; D058851:GPI-Linked Proteins; D018072:Hair Cells, Auditory, Outer / Q000502:physiology*; D008562:Membrane Glycoproteins / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008822:Mice, Transgenic; D012980:Sodium Salicylate / Q000494:pharmacology
D000894:Anti-Inflammatory Agents, Non-Steroidal; D016326:Extracellular Matrix Proteins; D058851:GPI-Linked Proteins; D008562:Membrane Glycoproteins; C105350:Tecta protein, mouse; D012980:Sodium Salicylate