title: Spontaneous reversibility of damage to outer hair cells after sodium salicylate induced ototoxicity.
abstract: BACKGROUND
  High sodium salicylate doses can cause reversible hearing loss and tinnitus, possibly due to reduced outer hair cell electromotility. Sodium salicylate is known to alter outer hair cell structure and function. This study determined the reversibility and cochlear recovery time after administration of an ototoxic sodium salicylate dose to guinea pigs with normal cochlear function.
  
  
  METHODS
  Prospective experimental investigation.
  
  
  METHODS
  All animals received a single 500 mg sodium salicylate dose, but with different durations of action. Function was evaluated before drug administration and immediately before sacrifice. Cochleae were processed and viewed using scanning electron microscopy.
  
  
  RESULTS
  Changes in outer hair cell function were observed to be present 2 hours after drug administration, with recovery of normal anatomy beginning after 24 hours. Subsequently, derangement and distortion of cilia reduced, with effects predominantly in row three. At 168 hours, cilia were near-normal but with mild distortions which interfered with normal cochlear physiology.
  
  
  CONCLUSIONS
  Ciliary changes persisted for up to 168 hours after ototoxic sodium salicylate administration.
authors.affiliation: Department of Speech Therapy, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: I
authors.initials: I
authors.lastname: de Almeida-Silva
authors.forename: J A A
authors.initials: JA
authors.lastname: de Oliveira
authors.forename: M
authors.initials: M
authors.lastname: Rossato
authors.forename: F Fiacadori
authors.initials: FF
authors.lastname: Salata
authors.forename: M A
authors.initials: MA
authors.lastname: Hyppolito
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects*; D002923:Cilia / Q000187:drug effects / Q000473:pathology / Q000648:ultrastructure; D003051:Cochlea / Q000187:drug effects / Q000648:ultrastructure; D004305:Dose-Response Relationship, Drug; D016057:Evoked Potentials, Auditory, Brain Stem / Q000187:drug effects / Q000502:physiology; D005260:Female; D006168:Guinea Pigs; D018072:Hair Cells, Auditory, Outer / Q000187:drug effects* / Q000473:pathology / Q000648:ultrastructure; D034381:Hearing Loss / Q000139:chemically induced* / Q000473:pathology / Q000517:prevention & control; D008855:Microscopy, Electron, Scanning; D017084:Otoacoustic Emissions, Spontaneous / Q000187:drug effects; D011446:Prospective Studies; D020127:Recovery of Function; D012980:Sodium Salicylate / Q000009:adverse effects*; D013997:Time Factors; D014012:Tinnitus / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D012980:Sodium Salicylate