title: Acute spiral ganglion cell degeneration following acoustic overstimulation: an experimental study.
abstract: BACKGROUND
  To evaluate acoustic overstimulation-induced spiral ganglion cell (SGC) degeneration, and determine the relationship between the duration of acoustic overstimulation and rate of SGC degeneration.
  
  
  METHODS
  Fifteen guinea pigs were randomized equally to 4 experimental groups, which were exposed to different durations (7.5, 15, 30 and 60 min) of acoustic overstimulation (120 dB at 4 kHz), and a control group. Every bulla was examined histopathologically and immunohistochemically. A quantitative and statistical analysis of acidophilic and TUNEL-positive SGCs was performed.
  
  
  RESULTS
  In the control group, 2.1% of SGCs were acidophilic and no TUNEL-positive SGC was detected. In contrast, a statistically significant number of acidophilic (p = 0.000) and TUNEL-positive SGCs (p = 0.002) was determined in the experimental groups. Moreover, a positive correlation between the duration of acoustic overstimulation and acidophilic SGCs (p = 0.000), and a statistically significant relationship between the duration of acoustic overstimulation and TUNEL-positive SGCs (p = 0.000) were demonstrated.
  
  
  CONCLUSIONS
  Acoustic overstimulation may induce acute SGC degeneration. A positive correlation was determined between the duration of acoustic overstimulation and rate of degenerated SGCs.
authors.affiliation: Department of Otolaryngology - Head and Neck Surgery, Celal Bayar University, Manisa, Turkey. gorkemeskiizmir@yahoo.com
authors.forename: Görkem
authors.initials: G
authors.lastname: Eskiizmir
authors.forename: Ali Vefa
authors.initials: AV
authors.lastname: Yücetürk
authors.forename: Sevinç
authors.initials: S
authors.lastname: Inan
authors.forename: Seren Gülşen
authors.initials: SG
authors.lastname: Gürgen
mesh_terms: D000208:Acute Disease; D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D004195:Disease Models, Animal; D006168:Guinea Pigs; D006317:Hearing Loss, Noise-Induced / Q000473:pathology*; D020287:In Situ Nick-End Labeling; D009410:Nerve Degeneration / Q000473:pathology*; D009622:Noise / Q000009:adverse effects*; D011984:Sensory Receptor Cells / Q000473:pathology; D013136:Spiral Ganglion / Q000473:pathology*