Cochlear dysfunction in the jerker mouse.

K P Steel; G R Bock

doi:10.1037//0735-7044.97.3.381

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PubMed · 6871029

Cochlear dysfunction in the jerker mouse.

K P Steel·G R Bock

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Abstract

Surface preparations show that the jerker (je/je) mutant mouse has a normal total number of cochlear hair cells when young but that these progressively degenerate with increasing age. However, no gross 8th nerve action potentials or cochlear microphonics could be detected at the round window in 12-20-day-old mutants, although many hair cells still appear to be intact at these ages. Light microscopy of surface preparations is apparently a poor indicator of the functional state of hair cells, at least in genetically determined inner ear defects. The endocochlear potential (EP) was significantly higher in the mutants than in controls during the maturation of the cochlea. During anoxia induced in adults, EP fell to a significantly less negative value in mutants than in control mice. This abnormality in the anoxia potential probably reflects an organ of Corti abnormality.

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Age Factors Animals Auditory Perception Auditory Threshold Cochlea Cochlear Microphonic Potentials Cochlear Nerve Hair Cells, Auditory Mice Mice, Neurologic Mutants Nerve Degeneration Organ of Corti Pitch Perception Journal Article Research Support, Non-U.S. Gov't

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K P Steel, G R Bock. 1983. Cochlear dysfunction in the jerker mouse.. https://doi.org/10.1037/%2F0735-7044.97.3.381

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