A freeze-etch study of the effects of filipin on liposomes and human erythrocyte membranes.
A freeze-etch study of the effects of filipin on liposomes and human erythrocyte membranes.
复制标题
菲律宾素对脂质体和人红细胞膜影响的冷冻蚀刻研究。
DOI：
10.1016/0005-2736(73)90430-6
复制
发表时间：
1973
期刊：
影响因子：
--
通讯作者：
S. Kinsky
中科院分区：
文献类型：
--
作者：
T. Tillack;S. Kinsky
先前的研究表明，在磷脂-胆固醇脂质体和经多烯抗生素菲利平处理的红细胞细胞膜中存在圆形负染病变；这些病变在形态上与免疫溶解后的红细胞膜中发现的相似。菲利平还被证明可以导致含有胆固醇的脂质体释放葡萄糖和大分子酶标记物。在目前的研究中，冷冻蚀刻被用来确定这些病变是否是穿透膜的孔。与抗生素孵育后，脂质体中可见结构变化(凹坑、甜甜圈形状的凹坑和突起)，其形成依赖于胆固醇的存在；红细胞膜中的纤毛蛋白也会产生类似的变化。然而，对外表面和内表面以及外和内断裂面的检查表明，这些结构变化不能等同于横向孔洞。因此，阴性染色的病变不太可能是通过脂质体双层和红细胞膜的稳定开放通道，这些双层和红细胞膜负责逃逸标记化合物和细胞质成分。
Previous investigations have demonstrated the presence of circular negatively stained lesions in phospholipid-cholesterol liposomes and in the cell membranes of erythrocytes that have been treated with the polyene antibiotic, filipin; these lesions are morphologically similar to those found in erythrocyte cell membranes after immune lysis. Filipin has been shown also to cause release of both glucose and macromolecular enzyme markers from liposomes that contain cholesterol. In the present study, freeze-etching was employed to determine if these lesions are holes through the membrane. Structural alterations (pits, doughnut-shaped craters and protrusions), whose formation was dependent on the presence of cholesterol, were demonstrable in liposomes after incubation with the antibiotic; analogous changes were also produced by filipin in erythrocyte membranes. However, examination of outer and inner surfaces, and outer and inner fracture faces, did not indicate that these structural alterations could be equated with transverse holes. It is, therefore, unlikely that the negatively stained lesions represent stable open channels through liposomal bilayers and erythrocyte membranes which are responsible for the escape of marker compounds and cytoplasmic constituents.