title: Lipids of human retina, retinal pigment epithelium, and Bruch's membrane/choroid: comparison of macular and peripheral regions.
abstract: OBJECTIVE
  To understand the difference between macular and peripheral regions, tissue samples of human retina, retinal pigment epithelium, and Bruch's membrane/choroid were dissected and analyzed for lipid composition.
  
  
  METHODS
  To facilitate dissections and enhance the recovery of tissues, eyecups were prefixed for 1 hour in 10% formalin (pH 7). Lipids were extracted from 4-mm trephined punches of tissues and analyzed by high-performance liquid chromatography. After separation of neutral lipids and phospholipids, total fatty acids in both lipid classes were quantitated.
  
  
  RESULTS
  The major phospholipid classes in retina, retinal pigment epithelium, and Bruch's membrane/choroid were phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl inositol, and phosphatidyl serine; the major fatty acids were palmitic (16:0), stearic (18:0), and oleic (18:1). Although the three tissues had similar total fatty acid and phospholipid components, their relative compositions were different. Neutral lipid/phospholipid ratios in retinal pigment epithelium and Bruch's membrane/choroid were almost three times higher than in the retina.
  
  
  CONCLUSIONS
  This study provides information about the lipid composition of macular and peripheral regions of the human retina, retinal pigment epithelium, and Bruch's membrane/choroid. The methodology employed enabled study of lipids in small amounts of tissue, which will be of value in investigating the biochemical aspects of age-related macular degeneration.
authors.affiliation: Cullen Eye Institute, Baylor College of Medicine, Houston, Texas 77030.
authors.forename: H G
authors.initials: HG
authors.lastname: Gülcan
authors.forename: R A
authors.initials: RA
authors.lastname: Alvarez
authors.forename: M B
authors.initials: MB
authors.lastname: Maude
authors.forename: R E
authors.initials: RE
authors.lastname: Anderson
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016570:Bruch Membrane / Q000737:chemistry; D002829:Choroid / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D008055:Lipids / Q000032:analysis*; D008875:Middle Aged; D010857:Pigment Epithelium of Eye / Q000737:chemistry*; D012160:Retina / Q000737:chemistry*; D014602:Uvea / Q000737:chemistry*
chemical_list: D008055:Lipids