Schrier S L
Department of Medicine, Stanford University, CA 94305-5112.
J Lab Clin Med. 1987 Dec;110(6):791-7.
To evaluate the membrane events that take place during red blood cell shape change, the deformability of resealed ghosts was studied in the ektacytometer while alterations in ghost shapes were produced. By studying ghosts in the ektacytometer it is possible to assess small changes in membrane dynamic rigidity free of the complicating factors that exist in intact red blood cells, such as concerns over the ratio of surface area to volume and the internal viscosity. Ghosts resealed in isotonic buffers are echinocytic, but addition of magnesium-adenosine triphosphate converts them to discocytes. This conversion to discocytosis was accompanied by an increase in membrane rigidity. Addition of vanadate along with magnesium-adenosine triphosphate blocked the conversion of echinocytic ghosts to discocytes, and in parallel blocked the accompanying increase in rigidity. Monospecific rabbit antispectrin antibody was resealed within ghosts and produced the anticipated increase in membrane rigidity. Morphologic evaluation revealed that such ghosts had changed from echinocytes to discocytes. Therefore two very different methods were used to convert normally echinocytic ghosts into discocytic ghosts, and in both cases the shape change was accompanied by an increase in ghost rigidity. These experiments indicate that in isotonically resealed ghosts, the discocytic shape is achieved as a consequence of membrane protein changes that produce an increase in membrane rigidity.
为了评估红细胞形状改变过程中发生的膜事件，我们在红细胞变形仪中研究了重封血影的变形能力，同时使血影形状发生改变。通过在红细胞变形仪中研究血影，可以评估膜动态刚性的微小变化，而不受完整红细胞中存在的复杂因素影响，如表面积与体积之比以及内部粘度等问题。在等渗缓冲液中重封的血影呈棘状细胞形态，但添加镁 - 三磷酸腺苷会将它们转变为盘状细胞。这种向盘状细胞的转变伴随着膜刚性的增加。同时添加钒酸盐和镁 - 三磷酸腺苷会阻止棘状血影向盘状细胞的转变，并且同时阻止伴随的刚性增加。将单特异性兔抗血影蛋白抗体重封在血影内会使膜刚性出现预期的增加。形态学评估显示，此类血影已从棘状细胞转变为盘状细胞。因此，我们使用了两种截然不同的方法将正常的棘状血影转变为盘状血影，并且在这两种情况下，形状改变都伴随着血影刚性的增加。这些实验表明，在等渗重封的血影中，盘状细胞形态是由于膜蛋白变化导致膜刚性增加而形成的。
