Linked Life Data

17425569

Source:http://linkedlifedata.com/resource/pubmed/id/17425569

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2007-4-11
pubmed:abstractText
The goals were to study the physiological effects of auditory nerve myelinopathy in chinchillas and to test the hypothesis that myelin abnormalities could account for auditory neuropathy, a hearing disorder characterized by absent auditory brainstem responses (ABRs) with preserved outer hair cell function. Doxorubicin, a cytotoxic drug used as an experimental demyelinating agent, was injected into the auditory nerve bundle of 18 chinchillas; six other chinchillas were injected with vehicle alone. Cochlear microphonics, compound action potentials (CAPs), inferior colliculus evoked potentials (IC-EVPs), cubic distortion product otoacoustic emissions and ABRs were recorded before and up to 2 months after injection. Cochleograms showed no hair cell loss in any of the animals and measures of outer hair cell function were normal (cubic distortion product otoacoustic emissions) or enhanced (cochlear microphonics) after injection. ABR was present in animals with mild myelin damage (n = 10) and absent in animals with severe myelin damage that included the myelin surrounding spiral ganglion cell bodies and fibers in Rosenthal's canal (n = 8). Animals with mild damage had reduced response amplitudes at 1 day, followed by recovery of CAP and enhancement of the IC-EVP. In animals with severe damage, CAP and IC-EVP thresholds were elevated, amplitudes were reduced, and latencies were prolonged at 1 day and thereafter. CAPs deteriorated over time, whereas IC-EVPs partially recovered; latencies remained consistently prolonged despite changes in amplitudes. The results support auditory nerve myelinopathy as a possible pathomechanism of auditory neuropathy but indicate that myelinopathy must be severe before physiological measures are affected.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0953-816X
pubmed:author
pubmed:issnType
Print
pubmed:volume
25
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1437-46
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Physiological effects of auditory nerve myelinopathy in chinchillas.
pubmed:affiliation
Otolaryngology Department, Audiology Unit, El-Minia University Hospitals, El-Minia University, El-Minia, Egypt.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't