The relationship between outer hair cell loss and hearing loss in rats exposed to styrene

Details

• Personal Author:
  Chen G-D ; Henderson D ; Tanaka C
• Description:
  Outer hair cells (OHCs) are known to contribute to the cochlear amplifier. However, the relationship between cochlear amplification and number of OHC is still unclear. There are examples of normal thresholds with missing OHCs and conversely, elevated thresholds with a normal population of OHCs. Styrene targets OHCs starting from the third row, resulting in apoptotic cell death of the targeted cells. However, the remaining OHCs and IHCs appeared intact. IHC death did not occur until all 3 rows of OHCs were missing. Thus, the styrene-injured cochlea may be a good model for study of the relationship between cochlear amplification and OHC number. Our results showed that loss of OHCs up to 1/3 caused only a slight permanent threshold shift (PTS). in some cases, 1/3 of OHCs were missing without any observable biological consequences, indicating that normal cochlear amplification does not require a complete set of OHCs and 2/3 of normally functioning OHCs are sufficient to maintain normal cochlear sensitivity. When OHC loss increased from 1/3 to 2/3, PTS increased gradually to about 40 dB. the hearing loss did not continue to increase with OHC loss in the range from 2/3 to 100%. The data indicate that the gain of the cochlear amplifier is not 'all or none' in a certain range (1/3 to 2/3 OHC loss), the gain is OHC number dependent. [Description provided by NIOSH]
• Subjects:
  Animals Hearing Hearing Loss Hearing Loss, Noise-Induced Laboratories Noise Occupational Health Safety Styrene
• Keywords:
  Cell-damage Cell-function Cellular-function Exposure-levels Hearing-disorders Hearing-loss Laboratory-animals Noise-exposure Noise-induced-hearing-loss Styrenes
• ISSN:
  0742-3152
• Publisher:
  Association for Research in Otolaryngology
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Abstract or Summary
• Place as Subject:
  Arizona ; Missouri ; New York ; OSHA Region 2 ; OSHA Region 7 ; OSHA Region 9
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  31
• NIOSHTIC Number:
  nn:20041697
• Citation:
  Abstr Midwinter Res Meet Assoc Res Otolaryngol 2008 Feb; 31:173
• Editor(s):
  Santi PA
• Federal Fiscal Year:
  2008
• NORA Priority Area:
  Manufacturing ; Wholesale and Retail Trade
• Performing Organization:
  Washington University, St. Louis
• Peer Reviewed:
  False
• Start Date:
  20000401
• Source Full Name:
  Abstracts of the 31st Midwinter Research Meeting of the Association for Research in Otolaryngology, Febuary 16-21, 2008, Phoenix, Arizona
• End Date:
  20130914
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:a24827bba10bc4b85eccb08bc8e647a0a09005346a5a797c06ab6e5c5d68b710c292e332628bc6bdca16bf5dba7ae25885d28dfbf7827ec89d401446ad46819c
• Download URL:
  https://stacks.cdc.gov/view/cdc/194188/cdc_194188_DS1.pdf
• File Type:
  [PDF - 26.47 KB ]