Author
Byrdwell, William | |
BORCHMAN, D - UNIV LOUISVILLE KENTUCKY |
Submitted to: Association for Research in Vision and Ophthalmology
Publication Type: Abstract Only Publication Acceptance Date: 5/11/1997 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Molecular species of dihydrosphingomyelins (DHS) and sphingomyelins (SPM) of membranes of the human lens were identified. High Performance Liquid Chromatography (HPLC) was performed using a quaternary pump system. The column was an Adsorbosphere NH2, 4.6 mm x 25 cm, 5 micro m particle size. A Finnigan MAT SSQ 710C mass spectrometer (MS) was fitted with atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI) sources for APCI-MS and ESI-MS experiments, respectively. Sphingolipids of the human lens were determined to be composed of 76.9% DHS species and 23.1% SPM species. The most abundant DHS molecular species were 16:0 and 24:1 DHS, representing 57.8% and 23.3%, respectively. Lesser amounts of 24:0 (=5.9%), 22:0 (=2.8%), 22:1 (=2.8%), 18:0 (=0.8%), 14:0 (=4.6%) and other DHS species were identified. The most abundant SPM molecular species were 16:0 and 24:1 SPM, representing 53.9% and 17.6%, respectively. Lesser amounts of 24:0 (=12.6%), 22:0 (=2.7%), 22:1 (=2.4%), 18:0 (=0.7%), 14:0 (=7.2%) and other SPM species were identified. LC-APCI/MS allowed identification of the molecular species of DHS and SPM, which is necessary for characterization of human lens membranes. The very high degree of saturation in the hydrocarbons of the major human lens phospholipids would be expected to render lens membranes impervious to oxidation; predisposed to high order and stability; highly impermeable; and non-chromagenic. |