title: Aquaporin-2 in the human endolymphatic sac.
abstract: OBJECTIVE
  To detect and localize aquaporin-2 (AQP-2), a water channel regulated by the antidiuretic hormone, in human endolymphatic sac.
  
  
  METHODS
  Human endolymphatic sacs were sampled during removal of vestibular schwannomas via a translabyrinthine approach. Samples were immediately fixed in 10% formalin (24 h) and embedded in paraffin; in situ hybridization and immunohistochemistry were performed with an AQP-2-specific probe and a polyclonal antibody.
  
  
  RESULTS
  Both AQP-2 mRNA and protein were detected in the epithelium of the endolymphatic sac. AQP-2 immunostaining was mainly cytoplasmic, suggesting that most AQP-2 was located in intracellular pools.
  
  
  CONCLUSIONS
  In the endolymphatic sac, AQP-2 probably participates in the homeostasis of endolymph; the possibility of reducing the volume of endolymph by inhibiting its expression and membranous insertion using an antidiuretic hormone inhibitor represents a new therapeutic approach for the treatment of Ménière's disease.
authors.affiliation: INSERM EMI-U 0112, Faculté Xavier Bichat, Paris, France. vincent.couloigner@rdb.ap-hop-paris.fr
authors.forename: Vincent
authors.initials: V
authors.lastname: Couloigner
authors.forename: Dominique
authors.initials: D
authors.lastname: Berrebi
authors.forename: Marie
authors.initials: M
authors.lastname: Teixeira
authors.forename: Régine
authors.initials: R
authors.lastname: Paris
authors.forename: Agnès
authors.initials: A
authors.lastname: Florentin
authors.forename: Alexis
authors.initials: A
authors.lastname: Bozorg Grayeli
authors.forename: Françoise
authors.initials: F
authors.lastname: Cluzeaud
authors.forename: Olivier
authors.initials: O
authors.lastname: Sterkers
authors.forename: Michel
authors.initials: M
authors.lastname: Peuchmaur
authors.forename: Evelyne
authors.initials: E
authors.lastname: Ferrary
mesh_terms: D051399:Aquaporin 2; D020346:Aquaporins / Q000032:analysis*; D003593:Cytoplasm / Q000737:chemistry; D004712:Endolymphatic Sac / Q000737:chemistry*; D004848:Epithelium / Q000737:chemistry; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D014722:Vestibule, Labyrinth / Q000737:chemistry
chemical_list: C496023:AQP2 protein, human; D051399:Aquaporin 2; D020346:Aquaporins