Borchman D, Ozaki Y, Lamba O P, Byrdwell W C, Czarnecki M A, Yappert M C
Department of Ophthalmology and Visual Sciences, University of Louisville, KY 40292, USA.
Curr Eye Res. 1995 Jun;14(6):511-5. doi: 10.3109/02713689509003763.
Regional differences in human lens membrane lipid composition have been documented and could be responsible for alterations in the function of lens membranes. The phospholipid composition of epithelial membranes of human lenses has been shown to be different from that of fiber membranes. To establish lipid composition-membrane structure relationships, we have examined spectroscopically the structure of lipid membranes from human lens epithelium, cortex and nucleus. Near-infrared Fourier transform Raman spectroscopy was used to obtain the lipid structure of membranes in which the lipid composition was determined previously by 31P-NMR. The disorder (fluidity measured structurally) of the epithelium was evaluated to be 80%, whereas that of the lipids from the cortical and nuclear regions was 55%. The large size of the band at 1650 cm-1 arising from sphingolipids supported the compositional studies which indicate that the major component of human lens membranes is a sphingolipid. Sphingolipids probably account for the high degree of lipid order found in lens membranes. Epithelial membranes were found to contain more glycerolipids and less sphingolipids than fiber cell membranes. This compositional difference would be expected to disorder the epithelial membrane.
人类晶状体膜脂质组成的区域差异已有文献记载，可能是晶状体膜功能改变的原因。已表明人类晶状体上皮膜的磷脂组成与纤维膜不同。为了建立脂质组成与膜结构的关系，我们用光谱法研究了人类晶状体上皮、皮质和核的脂质膜结构。利用近红外傅里叶变换拉曼光谱获得脂质膜的脂质结构，其中脂质组成先前已通过31P-NMR测定。上皮的无序度（通过结构测量的流动性）评估为80%，而皮质和核区域脂质的无序度为55%。鞘脂在1650 cm-1处产生的大谱带支持了成分研究，该研究表明人类晶状体膜的主要成分是鞘脂。鞘脂可能是晶状体膜中高度脂质有序的原因。发现上皮膜比纤维细胞膜含有更多的甘油脂和更少的鞘脂。这种成分差异预计会使上皮膜无序。
