title: Influence of evoked HSP70 expression on hearing function of the cochlea in guinea pigs.
abstract: OBJECTIVE
  To investigate the effect of evoked heat shock protein 70 (HSP70) expression on the hearing function of the cochlea in guinea pigs.
  
  
  METHODS
  Guinea pigs were divided into pre-exposure group (pre-treated with white noise exposure at 100 dB SPL for 45 min) and none pre-exposure group. Auditory brainstem response (ABR) thresholds were recorded at 12, 60 and 108 h after the animals in both groups were exposed to loud white noise (125 dB SPL, 90 min).
  
  
  RESULTS
  HSP70 expression was evoked by pre-treatment with white noise (100 dB SPL, 45 min). There was no significant difference of ABR thresholds between the 2 groups (P>0.05) at 12 h after exposure to loud noise, while ABR thresholds became lower in pre-exposure group than in none pre-exposure group (P<0.01) at both 60 and 108 h. In the pre-exposure group, ABR thresholds at 108 h were significantly lower than that measured at 60 h (P<0.05), but which was not the case in none pre-exposure group.
  
  
  CONCLUSIONS
  HSP70 expression induced by pre-exposure to noise protects the hearing function of the cochlea in guinea pigs.
authors.affiliation: Department of Otolaryngology, 456 Hospital of PLA, Ji'nan 250031, China.
authors.forename: Xu-Wu
authors.initials: XW
authors.lastname: Wang
authors.forename: Xi-Jun
authors.initials: XJ
authors.lastname: Wang
authors.forename: Jiang-Shun
authors.initials: JS
authors.lastname: Song
authors.forename: He-Xin
authors.initials: HX
authors.lastname: Chen
authors.forename: Yu-Hong
authors.initials: YH
authors.lastname: Man
mesh_terms: D000818:Animals; D003051:Cochlea / Q000502:physiology*; D004594:Electrophysiology; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology; D006168:Guinea Pigs; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis*; D006309:Hearing / Q000502:physiology*; D009622:Noise; D013997:Time Factors
chemical_list: D018840:HSP70 Heat-Shock Proteins