Document Detail


Dosing study on the effectiveness of salicylate/N-acetylcysteine for prevention of noise-induced hearing loss.
MedLine Citation:
PMID:  20603572     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The efficacy of three different doses of sodium salicylate (SAL) in combination with one dose of N-acetylcysteine (NAC) to prevent noise-induced hearing loss was studied in chinchillas. After obtaining baseline-hearing thresholds, the chinchillas were randomly assigned to one of four treatment groups: three sets were injected intraperitoneally with 325 mg/kg NAC combined with 25, 50, or 75 mg/kg SAL, and a separate control group was injected with an equal volume of saline. Animals were injected twice daily for 2 days prior to and 1 hour before the noise exposure (6 hours to a 105-dB Standard Pressure Level octave band noise centered at 4 kHz). Immediate post-noise hearing thresholds were obtained followed by post-noise treatments at 1 hour then twice-daily for 2 days. Hearing tests continued at 1, 2, and 3 weeks post-noise, and immediately after the last hearing test, animals' cochleae were stained for hair cell counts. All the groups showed hearing improvement until week 2. However, at week 3, saline treated animals demonstrated a 17-33 dB SPL permanent threshold shift (PTS) across the test frequencies. Hearing loss was lowest in the 50 SAL/325 NAC mg/kg group (all frequencies, P < 0.001), and although PTS was reduced in the 25 and 75 mg/kg SAL dosage groups compared to the saline group, only the 75 mg/kg SAL group was significantly different at all but 2 kHz frequency. Coupled with the hearing loss, outer hair cell (OHC) loss was maximal in the 4-8 kHz cochlear region of saline treated animals. However, there was a substantial reduction in the mean OHC loss of the NAC plus 50 or 75 mg/kg (but not the 25 mg/kg) SAL groups. These findings suggest that SAL in combination with NAC is effective in reducing noise damage to the cochlea, but SAL has a relatively narrow therapeutic dosing window.
Authors:
John Coleman; Xinyan Huang; Jianzhong Liu; Richard Kopke; Ronald Jackson
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  Noise & health     Volume:  12     ISSN:  1463-1741     ISO Abbreviation:  Noise Health     Publication Date:    2010 Jul-Sep
Date Detail:
Created Date:  2010-07-06     Completed Date:  2010-09-23     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  9815620     Medline TA:  Noise Health     Country:  India    
Other Details:
Languages:  eng     Pagination:  159-65     Citation Subset:  IM    
Affiliation:
Spatial Orientation Centre, Department of Otolaryngology, Naval Medical Centre San Diego, 34800 Bob Wilson Drive, San Diego, CA 92134, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Acetylcysteine / administration & dosage*,  pharmacology
Analysis of Variance
Animals
Anti-Inflammatory Agents, Non-Steroidal / administration & dosage*,  pharmacology
Auditory Threshold / drug effects
Chinchilla
Disease Models, Animal
Drug Administration Schedule
Drug Combinations
Drug Evaluation, Preclinical
Evoked Potentials, Auditory, Brain Stem / drug effects
Female
Free Radical Scavengers / administration & dosage*,  pharmacology
Hair Cells, Auditory, Outer / drug effects,  pathology
Hearing Loss, Noise-Induced / diagnosis,  prevention & control*
Hearing Tests
Injections, Intraperitoneal
Random Allocation
Sodium Salicylate / administration & dosage*,  pharmacology
Sound Spectrography
Chemical
Reg. No./Substance:
0/Anti-Inflammatory Agents, Non-Steroidal; 0/Drug Combinations; 0/Free Radical Scavengers; 54-21-7/Sodium Salicylate; 616-91-1/Acetylcysteine

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Clubbing: The cumulative effect of noise exposure from attendance at dance clubs and night clubs on ...
Next Document:  Evaluation of annoyance from low frequency noise under laboratory conditions.