Return of auditory function following structural regeneration after acoustic trauma: behavioral measures from quail

Hear Res. 1994 Sep;79(1-2):1-16. doi: 10.1016/0378-5955(94)90122-8.

Abstract

After measuring baseline behavioral audiograms, three of four behaviorally trained quail and fifteen untrained cohorts were exposed to a 1.5-kHz octave-band noise at 116-dB SPL for 4 h. The trained birds were tested daily following the exposure and showed a steady recovery of absolute sensitivity with a return to normal absolute thresholds by post-exposure days 8-10. Thirteen untrained cohorts were sacrificed after various survival times to evaluate the structural condition of the ear. The cohorts all showed regeneration of sensory cells similar to that seen in chicks. The effects of repeated acoustic trauma on recovery of sensitivity were evaluated by re-exposing the three trained birds and two untrained cohorts 106 days after the first exposure. One of the trained birds was exposed a third time, 113 days following the second exposure. The findings demonstrate that, following acoustic trauma, normal sensitivity returns prior to complete structural regeneration of the sensory epithelium and that repeated acoustic trauma may increase the time course of recovery of normal hearing sensitivity.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acoustic Stimulation
  • Actin Cytoskeleton / metabolism
  • Actins / metabolism
  • Animals
  • Audiometry
  • Auditory Threshold / physiology*
  • Behavior, Animal / physiology
  • Coturnix
  • DNA / metabolism
  • Hair Cells, Auditory / cytology
  • Hair Cells, Auditory / pathology
  • Hair Cells, Auditory / physiology*
  • Hearing Loss, Noise-Induced / pathology
  • Hearing Loss, Noise-Induced / physiopathology*
  • Histocytochemistry
  • Immunohistochemistry
  • Microscopy, Fluorescence
  • Nerve Regeneration*
  • Temporal Bone / cytology
  • Temporal Bone / pathology

Substances

  • Actins
  • DNA