In:
Audiology and Neurotology, S. Karger AG, Vol. 13, No. 6 ( 2008), p. 388-395
Abstract:
To explore the role of nerve growth factor receptor p75 〈 sup 〉 NTR 〈 /sup 〉 during the terminal neuronal development of the mammalian cochlea the onset of hearing and the in vitro response of spiral ganglion neurites to neurotrophin 3 (NT-3), which is known to play a critical role during neonatal inner ear development, were investigated in p75 〈 sup 〉 NTR 〈 /sup 〉 -deficient mice (p75 〈 sup 〉 NTR 〈 /sup 〉 –/–). Auditory-evoked brain stem response recordings from p75 〈 sup 〉 NTR 〈 /sup 〉 –/– and wild-type (WT) littermates were measured from postnatal days (PD) 8 to 23. Additionally, spiral ganglion explants from p75 〈 sup 〉 NTR 〈 /sup 〉 –/– and WT animals were dissected and cultured in an organotypic tissue culture system. In both groups, spiral ganglion neurite outgrowth was analyzed with and without NT-3 supplementation. No significant differences in the onset of hearing of mutant mice compared to the WT mice were detected, and both groups showed a similar development of hearing until PD 23. After stimulation with NT-3, neurite outgrowth was enhanced in both p75 〈 sup 〉 NTR 〈 /sup 〉 –/– and WT mice. However, neurites from p75 〈 sup 〉 NTR 〈 /sup 〉 –/– spiral ganglion explants were longer in both culture conditions. Moreover, NT-3 did not significantly enhance neurite number in p75 〈 sup 〉 NTR 〈 /sup 〉 –/–, as it did in WT mice. P75 〈 sup 〉 NTR 〈 /sup 〉 has a remarkable influence on spiral ganglion neurite growth behavior. However, p75 〈 sup 〉 NTR 〈 /sup 〉 does not seem to be essential for the development of basic hearing function in the first 3 postnatal weeks.
Type of Medium:
Online Resource
ISSN:
1420-3030
,
1421-9700
Language:
English
Publisher:
S. Karger AG
Publication Date:
2008
detail.hit.zdb_id:
1481979-X
