Journal article
Lack of Neurotrophin 3 Causes Losses of Both Classes of Spiral Ganglion Neurons in the Cochlea in a Region-Specific Fashion
The Journal of neuroscience, Vol.17(16), pp.6213-6225
08/15/1997
DOI: 10.1523/JNEUROSCI.17-16-06213.1997
PMCID: PMC2693053
PMID: 9236232
Abstract
Essential functions of neurotrophin 3 (NT-3) in regulating afferent and efferent innervation of the cochlea have been characterized by comparison of normal and NT-3 mutant mice. NT-3 deficiency has striking, region-specific effects, with complete loss of sensory neurons in the basal turn and dramatic but incomplete neuronal loss in the middle and apical turns. The sensory innervation of inner and outer hair cells was reorganized in mutant animals. Instead of a strictly radial pattern of innervation, the axons of remaining sensory neurons projected spirally along the row of inner hair cells to innervate even the most basal inner hair cells. Innervation of outer hair cells was strongly reduced overall and was not detected in the basal turn. The presence of fibers extending to both inner and outer hair cells suggests that subsets of types I and II sensory neurons survive in the absence of NT-3. Likewise, projections of the cochlea to auditory nuclei of the brainstem were attenuated but otherwise present. Equally striking changes in efferent innervation were observed in mutant animals that closely mimicked the abnormal sensory innervation pattern. Despite these impressive innervation deficiencies, the morphology of the organ of Corti and the development of inner and outer hair cells appeared comparatively normal.
Details
- Title: Subtitle
- Lack of Neurotrophin 3 Causes Losses of Both Classes of Spiral Ganglion Neurons in the Cochlea in a Region-Specific Fashion
- Creators
- Bernd Fritzsch - Department of Biomedical Sciences, Creighton University, Omaha, Nebraska 68178Isabel Fariñas - Program in Neuroscience, Department of Physiology and Howard Hughes Medical Institute, University of California, San Francisco, California 94143−0724Louis F Reichardt - Program in Neuroscience, Department of Physiology and Howard Hughes Medical Institute, University of California, San Francisco, California 94143−0724
- Resource Type
- Journal article
- Publication Details
- The Journal of neuroscience, Vol.17(16), pp.6213-6225
- DOI
- 10.1523/JNEUROSCI.17-16-06213.1997
- PMID
- 9236232
- PMCID
- PMC2693053
- NLM abbreviation
- J Neurosci
- ISSN
- 0270-6474
- eISSN
- 1529-2401
- Language
- English
- Date published
- 08/15/1997
- Academic Unit
- Iowa Neuroscience Institute; Biology; Craniofacial Anomalies Research Center
- Record Identifier
- 9984070509502771
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