title: Effects of Noise Exposure on the Auditory Function of Ovariectomized Rats with Estrogen Deficiency.
abstract: OBJECTIVE
  The benefits of estrogen for the auditory function of women depend on a number of factors. In this study, we aimed to examine the impact of noise trauma on the auditory function of ovariectomized rats with estrogen deficiency.
  
  
  METHODS
  Twenty-eight young, female Sprague-Dawley rats were assigned to three groups (OVX+N, OVX-N, Sham+N). Rats in the OVX+N group and the OVX-N group underwent bilateral ovariectomy (OVX); the OVX+N group alone was also exposed to white noise (N) of 115 dB SPL for 8 hours a day over 14 days. The Sham+N group consisted of rats with intact ovaries that were exposed to the same noise. The auditory function of all rats was measured before treatment and after noise exposure by the signal-to-noise ratio (SNR) of distortion-product otoacoustic emissions (DPOAE) and the threshold of auditory-evoked brainstem response (ABR).
  
  
  RESULTS
  The Sham+N group (intact ovaries, noise-exposed) had worse auditory function than the OVX-N group (ovariectomy, no noise). The OVX+N group had decreased SNRs of DPOAE and increased ABR thresholds relative to the Sham+N group.
  
  
  CONCLUSIONS
  Noise exposure may cause greater damage to auditory function when estrogen levels are low in females.
authors.affiliation: Zhejiang Chinese Medical University, College of Medical Technology, Hangzhou, Zhejiang, China. ellawang@zcmu.edu.cn.
authors.forename: Xujun
authors.initials: X
authors.lastname: Hu
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Chi Chuen
authors.initials: CC
authors.lastname: Lau
mesh_terms: D000818:Animals; D001309:Auditory Threshold / Q000502:physiology*; D004195:Disease Models, Animal; D004967:Estrogens / Q000172:deficiency*; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D005260:Female; D009622:Noise; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*; D010052:Ovariectomy; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D004967:Estrogens