title: Identification of prostamides, fatty acyl ethanolamines, and their biosynthetic precursors in rabbit cornea.
abstract: Arachidonoyl ethanolamine (anandamide) and pros-taglandin ethanolamines (prostamides) are biologically active derivatives of arachidonic acid. Although available through different precursor phospholipids, there is considerable overlap between the biosynthetic pathways of arachidonic acid-derived eicosanoids and anandamide-derived prostamides. Prostamides exhibit physiological actions and are involved in ocular hypotension, smooth muscle contraction, and inflammatory pain. Although topical application of bimatoprost, a structural analog of prostaglandin F2α ethanolamide (PGF2α-EA), is currently a first-line treatment for ocular hypertension, the endogenous production of prostamides and their biochemical precursors in corneal tissue has not yet been reported. In this study, we report the presence of anandamide, palmitoyl-, stearoyl-, α-linolenoyl docosahexaenoyl-, linoleoyl-, and oleoyl-ethanolamines in rabbit cornea, and following treatment with anandamide, the formation of PGF2α-EA, PGE2-EA, PGD2-EA by corneal extracts (all analyzed by LC/ESI-MS/MS). A number of N-acyl phosphatidylethanolamines, precursors of anandamide and other fatty acyl ethanolamines, were also identified in corneal lipid extracts using ESI-MS/MS. These findings suggest that the prostamide and fatty acid ethanolamine pathways are operational in the cornea and may provide valuable insight into corneal physiology and their potential influence on adjacent tissues and the aqueous humor.
authors.affiliation: Manchester Pharmacy School, The University of Manchester, Faculty of Medical and Human Sciences, Manchester, UK.
authors.forename: Paula
authors.initials: P
authors.lastname: Urquhart
authors.affiliation: Department of Biological Sciences, Allergan Inc., Irvine, CA.
authors.forename: Jenny
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Biological Sciences, Allergan Inc., Irvine, CA.
authors.forename: David F
authors.initials: DF
authors.lastname: Woodward
authors.affiliation: Manchester Pharmacy School, The University of Manchester, Faculty of Medical and Human Sciences, Manchester, UK.
authors.forename: Anna
authors.initials: A
authors.lastname: Nicolaou
mesh_terms: D000818:Animals; D003315:Cornea / Q000378:metabolism*; D015232:Dinoprostone / Q000096:biosynthesis* / Q000737:chemistry / Q000378:metabolism*; D004983:Ethanolamines / Q000737:chemistry / Q000378:metabolism*; D011817:Rabbits
chemical_list: D004983:Ethanolamines; D015232:Dinoprostone
keywords: N-acyl phosphatidylethanolamine; N-acyl phosphatidylethanolamine phospholipase D; anandamide; cyclooxygenase; fatty acid amide hydrolase; liquid chromatography tandem mass spectrometry; ocular tissue; prostaglandin; prostaglandin ethanolamine; prostaglandin synthase