Greiner J V, Glonek T, Korb D R, Booth R, Leahy C D
Department of Ophthalmology, Harvard Medical School, Boston, Mass., USA.
Ophthalmic Res. 1996;28(1):44-9. doi: 10.1159/000267872.
The bulk of the lipid layer overlying the aqueous portion of the precorneal tear film is composed of polar and nonpolar components. The nonpolar lipids have been the subject of numerous studies; however, the polar lipids have remained relatively uncharacterized. The polar lipids are thought to contain surfactant phospholipids that are critical to the spreading of a lipid film over the aqueous layer, by providing an interface between this layer and the nonpolar lipids. The purpose of the present study is to identify and quantitate the phospholipid complement of meibomian gland secretion which provides the tear film with phospholipids. Meibomian gland secretion was collected from rabbits and phospholipids identified and quantitated by 31P nuclear magnetic resonance spectroscopy. Ten phospholipids were detected from meibomian gland secretion: diphosphatidylglycerol, dihydrosphingomyelin, ethanolamine plasmalogen, phosphatidylethanolamine (PE), phosphatidylserine, sphingomyelin, lysophosphatidylcholine, phosphatidylinositol, alkylacylphosphatidylcholine, and phosphatidylcholine (PC). The two major phospholipids were PC and PE, together comprising nearly 60% of the total phospholipid profile. The nature and relative concentrations of the meibomian gland secretion phospholipids are congruous with a surfactant role at the aqueous-lipid interface and, considering the physical chemistry of the tear film, suggest that the phospholipids should be organized in a very flat or planar configuration.
覆盖在角膜前泪膜水液部分之上的脂质层主要由极性和非极性成分组成。非极性脂质已成为众多研究的对象；然而，极性脂质仍相对未被充分表征。极性脂质被认为含有表面活性磷脂，这些磷脂通过在水液层和非极性脂质之间提供一个界面，对于脂质膜在水液层上的铺展至关重要。本研究的目的是鉴定和定量睑板腺分泌液中的磷脂成分，睑板腺分泌液为泪膜提供磷脂。从兔子身上收集睑板腺分泌液，并通过31P核磁共振波谱法对磷脂进行鉴定和定量。从睑板腺分泌液中检测到十种磷脂：双磷脂酰甘油、二氢鞘磷脂、乙醇胺缩醛磷脂、磷脂酰乙醇胺（PE）、磷脂酰丝氨酸、鞘磷脂、溶血磷脂酰胆碱、磷脂酰肌醇、烷基酰基磷脂酰胆碱和磷脂酰胆碱（PC）。两种主要的磷脂是PC和PE，它们一起占总磷脂谱的近60%。睑板腺分泌液磷脂的性质和相对浓度与在水液-脂质界面的表面活性剂作用一致，并且考虑到泪膜的物理化学性质，表明磷脂应以非常扁平或平面的构型排列。
