Journal article
Development and organization of polarity-specific segregation of primary vestibular afferent fibers in mice
Cell and tissue research, Vol.340(2), pp.303-321
05/2010
DOI: 10.1007/s00441-010-0944-1
PMCID: PMC2953634
PMID: 20424840
Abstract
A striking feature of vestibular hair cells is the polarized arrangement of their stereocilia as the basis for their directional sensitivity. In mammals, each of the vestibular end organs is characterized by a distinct distribution of these polarized cells. We utilized the technique of post-fixation transganglionic neuronal tracing with fluorescent lipid soluble dyes in embryonic and postnatal mice to investigate whether these polarity characteristics correlate with the pattern of connections between the endorgans and their central targets; the vestibular nuclei and cerebellum. We found that the cerebellar and brainstem projections develop independently from each other and have a non-overlapping distribution of neurons and afferents from E11.5 on. In addition, we show that the vestibular fibers projecting to the cerebellum originate preferentially from the lateral half of the utricular macula and the medial half of the saccular macula. In contrast, the brainstem vestibular afferents originate primarily from the medial half of the utricular macula and the lateral half of the saccular macula. This indicates that the line of hair cell polarity reversal within the striola region segregates almost mutually exclusive central projections. A possible interpretation of this feature is that this macular organization provides an inhibitory side-loop through the cerebellum to produce synergistic tuning effects in the vestibular nuclei. The canal cristae project to the brainstem vestibular nuclei and cerebellum, but the projection to the vestibulocerebellum originates preferentially from the superior half of each of the cristae. The reason for this pattern is not clear, but it may compensate for unequal activation of crista hair cells or may be an evolutionary atavism reflecting a different polarity organization in ancestral vertebrate ears.
Details
- Title: Subtitle
- Development and organization of polarity-specific segregation of primary vestibular afferent fibers in mice
- Creators
- Adel Maklad - Department of Anatomy, University of Mississippi Medical Center, Jackson, MS 39216 USASuzan Kamel - Department of Oral Biology, University of Missouri, Kansas, MO 64108 USAElaine Wong - Department of Biology, University of Iowa, Iowa, IA 52242 USABernd Fritzsch - Department of Biology, University of Iowa, Iowa, IA 52242 USA
- Resource Type
- Journal article
- Publication Details
- Cell and tissue research, Vol.340(2), pp.303-321
- DOI
- 10.1007/s00441-010-0944-1
- PMID
- 20424840
- PMCID
- PMC2953634
- NLM abbreviation
- Cell Tissue Res
- ISSN
- 0302-766X
- eISSN
- 1432-0878
- Publisher
- Springer-Verlag; Berlin/Heidelberg
- Language
- English
- Date published
- 05/2010
- Academic Unit
- Iowa Neuroscience Institute; Biology; Craniofacial Anomalies Research Center
- Record Identifier
- 9984070778402771
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