title: Possible implications of acid-sensing ion channels in ischemia-induced retinal injury in rats.
abstract: BACKGROUND
  Retinal ischemia in eyes with diabetic retinopathy and retinal vein occlusion leads to local tissue acidosis. Acid-sensing ion channels (ASICs) are expressed in photoreceptors and other neurons in the retina, and may play a role in acid-induced cell injury. The purpose of this study was to investigate the neuroprotective effects of amiloride, an ASIC blocker, on induced retinal ischemia in rats.
  
  
  METHODS
  Transient retinal ischemia was induced in male Long-Evans rats by the temporary ligation of the optic nerve. Just before the induction of ischemia, the experimental eyes underwent intravitreal injection of amiloride. On day 7, the retinal damage in eyes that underwent amiloride treatment (and in those that did not undergo the treatment) was evaluated by histology and electroretinogram (ERG).
  
  
  RESULTS
  Transient retinal ischemia caused retinal degeneration with thinning of the inner layer of the retina. The blockage of ASICs with amiloride significantly prevented retinal degeneration. ERG demonstrated that the reduction in a- and b-wave amplitudes induced by the transient retinal ischemia was significantly prevented by the application of amiloride.
  
  
  CONCLUSIONS
  The present study suggests that ASICs might, at least in part, play a pathophysiological role in ischemia-induced neurodegeneration. Blockage of ASICs may have a potential neuroprotective effect in ocular ischemic diseases.
authors.affiliation: Department of Ophthalmology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi 467-8601, Japan.
authors.forename: Takatomo
authors.initials: T
authors.lastname: Miyake
authors.forename: Akiko
authors.initials: A
authors.lastname: Nishiwaki
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Yasukawa
authors.forename: Shinya
authors.initials: S
authors.lastname: Ugawa
authors.forename: Shoichi
authors.initials: S
authors.lastname: Shimada
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Ogura
mesh_terms: D062565:Acid Sensing Ion Channels / Q000096:biosynthesis*; D000818:Animals; D004195:Disease Models, Animal; D004596:Electroretinography; D007511:Ischemia / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D051381:Rats; D020318:Rats, Long-Evans; D015427:Reperfusion Injury / Q000150:complications* / Q000378:metabolism / Q000503:physiopathology; D012160:Retina / Q000473:pathology / Q000503:physiopathology; D012164:Retinal Diseases / Q000209:etiology / Q000378:metabolism* / Q000503:physiopathology; D012171:Retinal Vessels / Q000503:physiopathology
chemical_list: D062565:Acid Sensing Ion Channels