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Different cellular and genetic basis of noise-related endocochlear potential reduction in CBA/J and BALB/cJ mice.

Authors :
Ohlemiller KK
Rosen AD
Rellinger EA
Montgomery SC
Gagnon PM
Source :
Journal of the Association for Research in Otolaryngology : JARO [J Assoc Res Otolaryngol] 2011 Feb; Vol. 12 (1), pp. 45-58. Date of Electronic Publication: 2010 Oct 05.
Publication Year :
2011

Abstract

The acute and permanent effects of noise exposure on the endocochlear potential (EP) and cochlear lateral wall were evaluated in BALB/cJ (BALB) inbred mice, and compared with CBA/J (CBA) and C57BL/6 (B6) mice. Two-hour exposure to broadband noise (4-45 kHz) at 110 dB SPL leads to a approximately 50 mV reduction in the EP in BALB and CBA, but not B6. EP reduction in BALB and CBA is reliably associated with characteristic acute cellular pathology in stria vascularis and spiral ligament. By 8 weeks after exposure, the EP in CBA mice has returned to normal. In BALBs, however, the EP remains depressed by an average approximately 10 mV, so that permanent EP reduction contributes to permanent threshold shifts in these mice. We recently showed that the CBA noise phenotype in part reflects the influence of a large effect quantitative trait locus on Chr. 18, termed Nirep (Ohlemiller et al., Hear Res 260:47-53, 2010b). While CBA "EP susceptibility" alleles are dominant to those in B6, examination of (B6 × BALB) F1 hybrid mice and (F1 × BALB) N2 backcross mice revealed that noise-related EP reduction and associated cell pathology in BALBs are inherited in an autosomal recessive manner, and are dependent on multiple genes. Moreover, while N2 mice formed from B6 and CBA retain strong correspondence between acute EP reduction, ligament pathology, and strial pathology, N2s formed from B6 and BALB include subsets that dissociate pathology of ligament and stria. We conclude that the genes and cascades that govern the very similar EP susceptibility phenotypes in BALB and CBA mice need not be the same. BALBs appear to carry alleles that promote more pronounced long term effects of noise on the lateral wall. Separate loci in BALBs may preferentially impact stria versus ligament.

Details

Language :
English
ISSN :
1438-7573
Volume :
12
Issue :
1
Database :
MEDLINE
Journal :
Journal of the Association for Research in Otolaryngology : JARO
Publication Type :
Academic Journal
Accession number :
20922451
Full Text :
https://doi.org/10.1007/s10162-010-0238-z