Sensitive period to acoustic trauma in the rat pup cochlea. Histological findings

Acta Otolaryngol. Mar-Apr 1980;89(3-4):317-22. doi: 10.3109/00016488009127143.


In a previous paper we demonstrated physiologically a sensitive period for acoustic trauma in the rat pup cochlea, with a maximum at 22 days of age. Seven or 60 days after noise exposure these 22-day exposed rats were used for light and electron microscopy. At 7 days, surface preparation revealed restricted damage to the basal cochlear coil, while with electron microscopy signs of cytoplasmic degeneration appeared in the great majority of basal coil structures. Two months after noise exposure these structures have completely degenerated. These results were discussed in terms of mechanical versus metabolic explanations of the critical period for acoustic trauma.

MeSH terms

  • Animals
  • Animals, Newborn / physiology*
  • Cochlea / growth & development
  • Cochlea / injuries
  • Cochlea / ultrastructure*
  • Endolymph / metabolism
  • Hair Cells, Auditory / metabolism
  • Hair Cells, Auditory / ultrastructure
  • Hearing Loss, Noise-Induced / pathology*
  • Male
  • Microscopy, Electron
  • Rats
  • Time Factors
  • Vascular Diseases / etiology