Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2007-6-18
pubmed:abstractText
The C57BL/6J mouse has been a useful model of presbycusis, as it displays an accelerated age-related peripheral hearing loss. The medial olivocochlear efferent feedback (MOC) system plays a role in suppressing cochlear outer hair cell (OHC) responses, particularly for background noise. Neurons of the MOC system are located in the superior olivary complex, particularly in the dorsomedial periolivary nucleus (DMPO) and in the ventral nucleus of the trapezoid body (VNTB). We previously discovered that the function of the MOC system declines with age prior to OHC degeneration, as measured by contralateral suppression (CS) of distortion product otoacoustic emissions (DPOAEs) in humans and CBA mice. The present study aimed to determine the time course of age changes in MOC function in C57s. DPOAE amplitudes and CS of DPOAEs were collected for C57s from 6 to 40 weeks of age. MOC responses were observed at 6 weeks but were gone at middle (15-30 kHz) and high (30-45 kHz) frequencies by 8 weeks. Quantitative stereological analyses of Nissl sections revealed smaller neurons in the DMPO and VNTB of young adult C57s compared with CBAs. These findings suggest that reduced neuron size may underlie part of the noteworthy rapid decline of the C57 efferent system. In conclusion, the C57 mouse has MOC function at 6 weeks, but it declines quickly, preceding the progression of peripheral age-related sensitivity deficits and hearing loss in this mouse strain.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9967
pubmed:author
pubmed:copyrightInfo
(c) 2007 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
503
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
593-604
pubmed:dateRevised
2007-12-3
pubmed:meshHeading
pubmed-meshheading:17559088-Acoustic Stimulation, pubmed-meshheading:17559088-Age Factors, pubmed-meshheading:17559088-Aging, pubmed-meshheading:17559088-Analysis of Variance, pubmed-meshheading:17559088-Animals, pubmed-meshheading:17559088-Auditory Pathways, pubmed-meshheading:17559088-Auditory Threshold, pubmed-meshheading:17559088-Brain Stem, pubmed-meshheading:17559088-Disease Models, Animal, pubmed-meshheading:17559088-Dose-Response Relationship, Radiation, pubmed-meshheading:17559088-Electroencephalography, pubmed-meshheading:17559088-Evoked Potentials, Auditory, Brain Stem, pubmed-meshheading:17559088-Feedback, pubmed-meshheading:17559088-Female, pubmed-meshheading:17559088-Functional Laterality, pubmed-meshheading:17559088-Male, pubmed-meshheading:17559088-Mice, pubmed-meshheading:17559088-Mice, Inbred C57BL, pubmed-meshheading:17559088-Mice, Inbred CBA, pubmed-meshheading:17559088-Otoacoustic Emissions, Spontaneous, pubmed-meshheading:17559088-Presbycusis, pubmed-meshheading:17559088-Species Specificity
pubmed:year
2007
pubmed:articleTitle
Auditory efferent feedback system deficits precede age-related hearing loss: contralateral suppression of otoacoustic emissions in mice.
pubmed:affiliation
Department of Otolaryngology, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642-8629, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural