title: Effect of aldosterone on cochlear Af9 expression and hearing in guinea pig.
abstract: CONCLUSIONS
  Af9 protein in cochlea may be closely related to endolymph regulation by aldosterone and thus may be involved in pathogenesis of endolymphatic hydrops (EH).
  
  
  OBJECTIVE
  EH is the pathological characteristic of Ménière's disease (MD). Aldosterone could induce EH, but its relationship with MD is still controversial. The aim of the present study is to investigate the Af9 protein expression in guinea pig cochlea and regulation of Af9 expression and cochlear function by aldosterone. The role of Af9 in pathogenesis of EH is discussed.
  
  
  METHODS
  Thirty guinea pigs were randomly divided into two groups. The treatment group was intraperitoneally injected with aldosterone 0.1 mg/kg/d for 5 days, while the control group was done with saline. Hearing and histomorphology of cochlea were examined. In addition, expression of Af9 protein was studied.
  
  
  RESULTS
  The hearing threshold of the treatment group was increased. EH was induced in 73% of guinea pigs in the treatment group, and no EH was found in the control group. Af9 protein was found in spiral limbus, stria vascularis, Reissner's membrane, organ of Corti and spiral ganglion in both groups. Af9 expression in cochlea decreased significantly at protein level after treatment by aldosterone.
authors.affiliation: a Department of Otolaryngology , The First Affiliated Hospital of Chongqing Medical University , Chongqing , China.
authors.forename: Li
authors.initials: L
authors.lastname: Qin
authors.affiliation: a Department of Otolaryngology , The First Affiliated Hospital of Chongqing Medical University , Chongqing , China.
authors.forename: Biyun
authors.initials: B
authors.lastname: Zhang
authors.affiliation: a Department of Otolaryngology , The First Affiliated Hospital of Chongqing Medical University , Chongqing , China.
authors.forename: Qianying
authors.initials: Q
authors.lastname: Wang
authors.affiliation: a Department of Otolaryngology , The First Affiliated Hospital of Chongqing Medical University , Chongqing , China.
authors.forename: Duanchao
authors.initials: D
authors.lastname: Li
authors.affiliation: a Department of Otolaryngology , The First Affiliated Hospital of Chongqing Medical University , Chongqing , China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Luo
authors.affiliation: a Department of Otolaryngology , The First Affiliated Hospital of Chongqing Medical University , Chongqing , China.
authors.forename: Shixun
authors.initials: S
authors.lastname: Zhong
mesh_terms: D000450:Aldosterone / Q000502:physiology*; D000818:Animals; D003051:Cochlea / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D018159:Endolymphatic Hydrops / Q000209:etiology / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D016057:Evoked Potentials, Auditory, Brain Stem; D006168:Guinea Pigs; D011897:Random Allocation
chemical_list: D000450:Aldosterone
keywords: Af9 protein; Endolymphatic hydrops; aldosterone; hearing