title: Endothelin-1 concentration is increased in the aqueous humour of patients with exfoliation syndrome.
abstract: BACKGROUND
  /aim: Endothelin 1 (ET-1) is considered the most potent vasoconstrictor in the body and the eye. This molecule may play a significant role in the pathobiology of exfoliation syndrome (XFS), a disorder characterised by a progressive iris vasculopathy. The purpose of this study was to investigate the concentration of ET-1 in the aqueous humour of cataract patients with and without XFS.
  
  
  METHODS
  Aqueous humour samples were obtained from 25 consecutive eyes of 25 cataract patients with XFS and an equal number of age matched controls during phacoemulsification cataract surgery. None of the subjects had elevated intraocular pressure or glaucoma. ET-1 concentration in the aqueous was measured using a specific immunoassay with 100% immunoreactivity for ET-1. Total aqueous humour protein concentration was measured with a microplate Coomassie blue based method and was correlated with ET-1 concentration.
  
  
  RESULTS
  Mean ET-1 concentration in the XFS aqueous samples (4.6 (SD 2.3) pg/ml) was significantly higher than that measured in the age matched control samples (2.8 (SD 1.71) pg/ml); (p = 0.006). Although total protein concentration was significantly elevated in the XFS samples (0.380 (SD 0.159) v 0.279 (SD 0.144) mg/ml in the controls); (p = 0.023), no correlation was found between aqueous ET-1 and total protein concentration (p = 0.730).
  
  
  CONCLUSIONS
  The increased concentration of ET-1 in the aqueous humour of XFS patients suggests that ET-1 may play a role in the pathobiology of XFS.
authors.affiliation: Dept of Biological Chemistry, Aristotle University, Thessaloniki, Greece. kaliakos@med.auth.gr
authors.forename: G G
authors.initials: GG
authors.lastname: Koliakos
authors.forename: A G P
authors.initials: AG
authors.lastname: Konstas
authors.forename: U
authors.initials: U
authors.lastname: Schlötzer-Schrehardt
authors.forename: G
authors.initials: G
authors.lastname: Hollo
authors.forename: D
authors.initials: D
authors.lastname: Mitova
authors.forename: D
authors.initials: D
authors.lastname: Kovatchev
authors.forename: S
authors.initials: S
authors.lastname: Maloutas
authors.forename: N
authors.initials: N
authors.lastname: Georgiadis
mesh_terms: D000368:Aged; D001082:Aqueous Humor / Q000737:chemistry*; D016022:Case-Control Studies; D002387:Cataract Extraction; D019332:Endothelin-1 / Q000032:analysis*; D017889:Exfoliation Syndrome / Q000150:complications / Q000378:metabolism*; D005136:Eye Proteins / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D011446:Prospective Studies
chemical_list: D019332:Endothelin-1; D005136:Eye Proteins