Auditory hair cells and spiral ganglion neurons regenerate synapses with refined release properties in vitro.
Proc Natl Acad Sci U S A
; 121(31): e2315599121, 2024 Jul 30.
Article
em En
| MEDLINE
| ID: mdl-39058581
ABSTRACT
Ribbon synapses between inner hair cells (IHCs) and type I spiral ganglion neurons (SGNs) in the inner ear are damaged by noise trauma and with aging, causing "synaptopathy" and hearing loss. Cocultures of neonatal denervated organs of Corti and newly introduced SGNs have been developed to find strategies for improving IHC synapse regeneration, but evidence of the physiological normality of regenerated synapses is missing. This study utilizes IHC optogenetic stimulation and SGN recordings, showing that, when P3-5 denervated organs of Corti are cocultured with SGNs, newly formed IHC/SGN synapses are indeed functional, exhibiting glutamatergic excitatory postsynaptic currents. When using older organs of Corti at P10-11, synaptic activity probed by deconvolution showed more mature release properties, closer to the specialized mode of IHC synaptic transmission crucial for coding the sound signal. This functional assessment of newly formed IHC synapses developed here, provides a powerful tool for testing approaches to improve synapse regeneration.
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Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Sinapses
/
Gânglio Espiral da Cóclea
Limite:
Animals
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article