Up-regulation of GAP-43 in the chinchilla ventral cochlear nucleus after carboplatin-induced hearing loss: correlations with inner hair cell loss and outer hair cell loss.
Hear Res
; 302: 74-82, 2013 Aug.
Article
en En
| MEDLINE
| ID: mdl-23707995
ABSTRACT
Inner ear damage leads to nerve fiber growth and synaptogenesis in the ventral cochlear nucleus (VCN). In this study, we documented the relationship between hair cell loss patterns and synaptic plasticity in the chinchilla VCN using immunolabeling of the growth associated protein-43 (GAP-43), a protein associated with axon outgrowth and modification of presynaptic endings. Unilateral round window application of carboplatin caused hair cell degeneration in which inner hair cells (IHC) were more vulnerable than outer hair cells (OHC). One month after carboplatin treatment (0.5-5 mg/ml), we observed varying patterns of cochlear hair cell loss and GAP-43 expression in VCN. Both IHC loss and OHC loss were strongly correlated with increased GAP-43 immunolabeling in the ipsilateral VCN. We speculate that two factors might promote the expression of GAP-43 in the VCN; one is the loss of afferent input through IHC or the associated type I auditory nerve fibers. The other occurs when the medial olivocochlear efferent neurons lose their cochlear targets, the OHC, and may as compensation increase their synapse numbers in the VCN.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Carboplatino
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Células Ciliadas Auditivas Externas
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Núcleo Coclear
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Proteína GAP-43
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Células Ciliadas Auditivas Internas
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Pérdida Auditiva
Límite:
Animals
Idioma:
En
Revista:
Hear Res
Año:
2013
Tipo del documento:
Article
País de afiliación:
Estados Unidos