title: A preliminary study of reduced expression of aquaporin-9 in the optic nerve of primate and human eyes with glaucoma.
abstract: OBJECTIVE
  To preliminarily test whether aquaporin (AQP)-9 is expressed in the primate and human optic nerve and whether glaucoma reduces its expression.
  
  
  METHODS
  The expression of AQP-4 and AQP-9 was immunohistochemically studied in the optic nerves of monkey eyes (an angle-laser-induced ocular hypertensive (OH) eye and a control fellow eye) and of human donor eyes (one control eye and one glaucomatous eye).
  
  
  RESULTS
  AQP-9 was immunoreactive throughout the entire region of the optic nerve in the monkey and human control eyes and was co-labeled with glial fibrillary acidic protein. In both the monkey OH and human glaucomatous optic nerves, the level of AQP-9 immunoreactivity was substantially reduced. AQP-4 was immunoreactive only in the retrobulbar region in both the monkey and human control optic nerves, whereas neither OH nor glaucoma affected the AQP-4 expression pattern.
  
  
  CONCLUSIONS
  As has been shown in rats, the optic nerve head in monkeys and humans expresses AQP-9 but not AQP-4. Elevated intraocular pressure or glaucoma reduces AQP-9 expression in the optic nerve. The decrease in the astrocytic expression of AQP-9 in the optic nerve could be implicated in the development of glaucomatous optic neuropathy.
authors.affiliation: Division of Ophthalmology, Department of Surgery, Kobe University Graduate School of Medicine, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Mizokami
authors.forename: Akiyasu
authors.initials: A
authors.lastname: Kanamori
authors.forename: Akira
authors.initials: A
authors.lastname: Negi
authors.forename: Makoto
authors.initials: M
authors.lastname: Nakamura
mesh_terms: D000368:Aged; D000818:Animals; D020346:Aquaporins / Q000096:biosynthesis*; D015415:Biomarkers / Q000378:metabolism; D004195:Disease Models, Animal; D018450:Disease Progression; D005902:Glaucoma, Open-Angle / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D008252:Macaca fascicularis; D008297:Male; D008856:Microscopy, Fluorescence; D009798:Ocular Hypertension / Q000378:metabolism* / Q000473:pathology; D009900:Optic Nerve / Q000378:metabolism* / Q000473:pathology; D011379:Prognosis
chemical_list: C109669:AQP9 protein, human; D020346:Aquaporins; D015415:Biomarkers