Humpert Christof, Baumann Martin
Institute of Physiology, RWTH Aachen, Germany.
Mol Membr Biol. 2003 Apr-Jun;20(2):155-62. doi: 10.1080/09687680307080.
Mechanical fluctuations on erythrocyte cell membranes wee measured by phase-contrast optics at the cell centre and cel rim. Intensity changes were digitized by a linear charge-coupled device array and both frequency spectra and autocorrelation functions were calculated to detect fluctuation characteristics at these areas. Validation was performed with glutaraldehydetreated cells. The influence of viscosity and membrane elasticity changes was evaluated by testing cells in solution of different osmolarities (239-392 mosmol I(-1)), and cells at different stages of diamide treatment (0.5-5.0 mmol I(-1)). The calculated membrane bending modulus of 1.4 E-19 J is in accordance with other findings. Despite an increase of endoplasmic viscosity, no homogeneous attenuation of the fluctuation amplitudes was observed, but a frequency shift was observed. Spectrin linkage caused by diamide has no effect on membrane fluctuations at the cell centre but it influences fluctuations at the cell rim, which can be explained by the higher membrane curvature at the cell rim compared with the lower, or even negative, membrane curvature at the cell centre.
通过相差光学显微镜在红细胞细胞膜的细胞中心和边缘测量机械波动。强度变化由线性电荷耦合器件阵列数字化，并计算频谱和自相关函数以检测这些区域的波动特征。用戊二醛处理的细胞进行验证。通过在不同渗透压（239 - 392 mosmol I(-1)）的溶液中测试细胞以及在不同阶段的二酰胺处理（0.5 - 5.0 mmol I(-1)）的细胞来评估粘度和膜弹性变化的影响。计算得出的膜弯曲模量为1.4 E - 19 J，与其他研究结果一致。尽管内质粘度增加，但未观察到波动幅度的均匀衰减，而是观察到了频率偏移。二酰胺引起的血影蛋白连接对细胞中心的膜波动没有影响，但会影响细胞边缘的波动，这可以通过细胞边缘较高的膜曲率与细胞中心较低甚至负的膜曲率来解释。
