title: Relation between Ocular Comfort, Arachidonic Acid Mediators, and Histamine.
abstract: Contact lenses are associated with discomfort during wear. This may be the result of stimulation of the ocular surface and production of pro-inflammatory mediators which are then released into the tears. This study examined changes in the concentration in tears of arachidonic acid metabolites (AAM) prostaglandins, cysteinyl leukotrienes, and resolvin-D1, as well as histamine in a general contact lens population in the morning and evening.
  
  
  
  Tears were collected twice a day (morning and evening) for up to 10 days on two different occasions (with and without contact lens wear) from 30 experienced contact lens wearers for analysis of AAM and a separate group (N = 33) for analysis of histamine. Ocular comfort was rated subjectively on an ordinal scale at each time of tear collection. Tears were analyzed using commercial immunoassay-based kits. Statistical analysis was performed using linear mixed model test.
  
  
  
  Ocular comfort decreased from morning to evening with and without contact lenses (p = 0.001), and the difference in comfort in the evening was greater with contact lens wear (80.9 ± 16.2 vs. 75.5 ± 16.8; p = 0.008). The total concentration of PGs (10.7 ± 10.8 ng/ml), cysteinyl leukotrienes (8.7 ± 0.38 ng/ml), resolvin-D1(1.6 ± 0.5 ng/ml), or histamine 13.8 ± 10.4 ng/ml) did not change during the day or during contact lens wear (p > 0.05).
  
  
  
  Prostaglandins, cysteinyl leukotrienes, resolvin-D1, or histamine concentrations did not alter in relation to changes in comfort of the eye during the day or during contact lens wear. These results suggest that release of these mediators is not responsible for contact lens discomfort.
authors.affiliation: a School of Optometry and Vision Science , University of New South Wales , Sydney , Australia.|b The Vision Cooperative Research Centre , Sydney , Australia.
authors.forename: Simin
authors.initials: S
authors.lastname: Masoudi
authors.affiliation: b The Vision Cooperative Research Centre , Sydney , Australia.|c Faculty of Medicine and Health Sciences , Macquarie University , Sydney , Australia.
authors.forename: Zhenjun
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: a School of Optometry and Vision Science , University of New South Wales , Sydney , Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: Willcox
mesh_terms: D000328:Adult; D016718:Arachidonic Acid / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D003263:Contact Lenses, Hydrophilic; D003316:Corneal Diseases / Q000378:metabolism*; D005260:Female; D006632:Histamine / Q000378:metabolism*; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism*; D008297:Male; D013666:Tears / Q000737:chemistry*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D016718:Arachidonic Acid; D006632:Histamine
keywords: Comfort; contact lens; histamine; leukotrienes; prostaglandins