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Journal of the Association for Research in Otolaryngology

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01-03-2009

Olivocochlear Neuron Central Anatomy Is Normal in α9 Knockout Mice

Authors: M. Christian Brown, Douglas E. Vetter

Published in: Journal of the Association for Research in Otolaryngology | Issue 1/2009

Abstract

Olivocochlear (OC) neurons were studied in a transgenic mouse with deletion of the α9 nicotinic acetylcholine receptor subunit. In this α9 knockout mouse, the peripheral effects of OC stimulation are lacking and the peripheral terminals of OC neurons under outer hair cells have abnormal morphology. To account for this mouse’s apparently normal hearing, it has been proposed to have central compensation via collateral branches to the cochlear nucleus. We tested this idea by staining OC neurons for acetylcholinesterase and examining their morphology in knockout mice, wild-type mice of the same background strain, and CBA/CaJ mice. Knockout mice had normal OC systems in terms of numbers of OC neurons, dendritic patterns, and numbers of branches to the cochlear nucleus. The branch terminations were mainly to edge regions and to a lesser extent the core of the cochlear nucleus, and were similar among the strains in terms of the distribution and staining density. These data demonstrate that there are no obvious changes in the central morphology of the OC neurons in α9 knockout mice and make less attractive the idea that there is central compensation for deletion of the peripheral receptor in these mice.

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Title: Olivocochlear Neuron Central Anatomy Is Normal in α9 Knockout Mice
Authors: M. Christian Brown
Douglas E. Vetter
Publication date: 01-03-2009
Publisher: Springer-Verlag
Published in: Journal of the Association for Research in Otolaryngology / Issue 1/2009
Print ISSN: 1525-3961
Electronic ISSN: 1438-7573
DOI: https://doi.org/10.1007/s10162-008-0144-9

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Springer Medicine

Olivocochlear Neuron Central Anatomy Is Normal in α9 Knockout Mice

Abstract

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Abstract

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