title: Hair cell and supporting cell response to acoustic trauma in the chick cochlea.
abstract: Damage to the chick cochlea in response to progressively increased periods of noise exposure was studied with scanning electron microscopy. Ten day-old chick hatchlings were exposed to a 1500 Hz pure tone at 120 dB SPL for 4, 8, 12, 24, and 48 h. Measurements of hair cell and supporting cell surface areas within a defined region of the cochlea showed that the average hair cell surface area decreased over the first 12 h of exposure. Between 12 h and 48 h there was no significant change in hair cell surface area. Supporting cells showed a corresponding increase in surface area over the same period. Noise damage first appeared after 4 h of exposure as a localized expansion of supporting cell surfaces near the inferior edge of the basilar papilla (BP). Between 8 and 12 h of exposure the supporting cell surface area increased dramatically and was visible throughout the noise damaged region. Hair cell expulsion was first seen after 12 h. Exposure to noise for 24-48 h resulted in further expansion of supporting cells, extensive expulsion of hair cells from the BP, and the appearance of a strip of noise damage along the superior, edge of the BP.
authors.affiliation: Department of Anatomy, Boston University School of Medicine, Massachusetts 02118.
authors.forename: D A
authors.initials: DA
authors.lastname: Cotanche
authors.forename: C E
authors.initials: CE
authors.lastname: Dopyera
mesh_terms: D000818:Animals; D002645:Chickens; D006198:Hair Cells, Auditory / Q000648:ultrastructure*; D006317:Hearing Loss, Noise-Induced / Q000473:pathology*; D007760:Labyrinth Supporting Cells / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning; D009925:Organ of Corti / Q000648:ultrastructure*; D013997:Time Factors