The ultrastructure of lipid-depleted rod photoreceptor membranes.
The ultrastructure of lipid-depleted rod photoreceptor membranes.
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脂质消耗的杆光感受器膜的超微结构。
DOI：
10.1083/jcb.63.2.587
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发表时间：
1974-11
期刊：
影响因子：
--
通讯作者：
Hall MO
中科院分区：
文献类型：
--
作者：
Nir I;Hall MO
用电子显微镜研究了脂质耗竭的视网膜视杆细胞感光膜的结构。用丙酮、氯仿-甲醇和酸化的氯仿-甲醇彻底提取醛固定的视网膜。通过薄层色谱和脂肪酸分析评价了预固定对脂质可提取性的影响。用戊二醛预固定使得38%的磷脂不可提取，而甲醛固定后仅7%不可提取。嵌入视网膜中的脂质保留，可聚合的戊二醛-尿素混合物允许比较OsO 4与脂质耗尽的膜和杆盘膜，其中包含所有的脂质的相互作用。电子密度的降低和脂质耗尽组织中膜精细结构的恶化与脂质提取的程度相关。这些观察结果表明的作用的脂质双层的膜结构的超微结构可视化与OsO 4。提取的组织的负染色薄切片揭示了脂质耗尽的杆膜中的亚结构。这些亚结构可能是视蛋白分子，视蛋白分子是视网膜视杆细胞膜的主要蛋白质成分。
The structure of lipid-depleted retinal rod photoreceptor membranes was studied by means of electron microscopy. Aldehyde-fixed retinas were exhaustively extracted with acetone, chloroform-methanol, and acidified chloroform-methanol. The effect of prefixation on the extractability of lipids was evaluated by means of thin-layer chromatography and fatty acid analysis. Prefixation with glutaraldehyde rendered 38% of the phospholipids unextractable, while only 7% were unextractable after formaldehyde fixation. Embedding the retina in a lipid-retaining, polymerizable glutaraldehyde-urea mixture allows a comparison of the interaction of OsO4 with lipid-depleted membranes and rod disk membranes which contain all their lipids. A decrease in electron density and a deterioration of membrane fine structure in lipid-depleted tissue are correlated with the extent of lipid extraction. These observations are indicative of the role of the lipid bilayer in the ultrastructural visualization of membrane structure with OsO4. Negatively stained thin sections of extracted tissue reveal substructures in the lipid-depleted rod membranes. These substructures are probably the opsin molecules which are the major protein component of retinal rod photoreceptor membranes.