Electron Microscopic Reconstruction of Neural Circuitry in the Cochlea.
Cell Rep
; 34(1): 108551, 2021 01 05.
Article
em En
| MEDLINE
| ID: mdl-33406431
ABSTRACT
Recent studies reveal great diversity in the structure, function, and efferent innervation of afferent synaptic connections between the cochlear inner hair cells (IHCs) and spiral ganglion neurons (SGNs), which likely enables audition to process a wide range of sound pressures. By performing an extensive electron microscopic (EM) reconstruction of the neural circuitry in the mature mouse organ of Corti, we demonstrate that afferent SGN dendrites differ in abundance and composition of efferent innervation in a manner dependent on their afferent synaptic connectivity with IHCs. SGNs that sample glutamate release from several presynaptic ribbons receive more efferent innervation from lateral olivocochlear projections than those driven by a single ribbon. Next to the prevailing unbranched SGN dendrites, we found branched SGN dendrites that can contact several ribbons of 1-2 IHCs. Unexpectedly, medial olivocochlear neurons provide efferent innervation of SGN dendrites, preferring those forming single-ribbon, pillar-side synapses. We propose a fine-tuning of afferent and efferent SGN innervation.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sinapses
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Gânglio Espiral da Cóclea
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Cóclea
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Dendritos
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Células Ciliadas Auditivas Internas
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Vias Neurais
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Neurônios
Limite:
Animals
Idioma:
En
Revista:
Cell Rep
Ano de publicação:
2021
Tipo de documento:
Article