Hirsch M, Tassin J, Noske W, Courtois Y
Laboratoire de Technologie Appliquée à la Microscopie Electronique, CNRS, Paris, France.
Exp Eye Res. 1989 Nov;49(5):717-27. doi: 10.1016/s0014-4835(89)80033-8.
Complete belts of intact tight junctions are thought to act as barriers to the movement of cholesterol in the plane of the plasma membrane. As cholesterol can be revealed by filipin-induced membrane deformations on freeze-fracture images, we studied the distribution of these deformation in cultured bovine corneal endothelial cells with incomplete belts of tight junctions. While the extent of filipin-induced deformations differed between individual cells, there is a homogeneous distribution of filipin-induced deformations on both sides of the incomplete junctional belt of endothelial cells. Our results suggest that cultured endothelial cells do not polarize cholesterol, possibly because of the incomplete tight-junctional barrier.
完整紧密连接带被认为是阻止胆固醇在质膜平面移动的屏障。由于在冷冻断裂图像上，菲律宾菌素诱导的膜变形可显示胆固醇，我们研究了这些变形在紧密连接带不完整的培养牛角膜内皮细胞中的分布情况。虽然菲律宾菌素诱导的变形程度在单个细胞之间存在差异，但在内皮细胞不完整连接带两侧，菲律宾菌素诱导的变形分布是均匀的。我们的结果表明，培养的内皮细胞不会使胆固醇极化，这可能是由于紧密连接屏障不完整所致。
