Effect of cholesterol in membranes. Pulsed nuclear magnetic resonance measurements of lipid lateral diffusion.
Effect of cholesterol in membranes. Pulsed nuclear magnetic resonance measurements of lipid lateral diffusion.
复制标题
胆固醇对细胞膜的影响。
作者：
G. Lindblom;L. Johansson;G. Arvidson
通过使用脉冲磁场梯度的脉冲核磁共振方法，可以在宏观排列的样品中直接测量双层中脂质的横向扩散系数[Lindblom， G., & Wennerström， H. (1977) Biophys。化学，6,167]。该技术已被用于研究胆固醇对蛋黄卵磷脂、棕榈酰卵磷脂和二酰卵磷脂的脂质扩散的影响。研究发现，胆固醇对磷脂扩散的影响很小。另一方面，胆固醇对双分子层的分子顺序和脂相结构有很大的影响。因此，胆固醇对脂膜稳定性起主导作用。
Lateral diffusion coefficients of lipids in a bilayer can be measured directly in a macroscopically aligned sample by use of a pulsed NMR method with pulsed magnetic field gradients [Lindblom, G., & Wennerström, H. (1977) Biophys. Chem. 6, 167]. This technique has been utilized to investigate the influence of cholesterol on the lipid diffusion of egg yolk lecithin, palmitoyloleoyllecithin, and dioleoyllecithin. It is found that cholesterol has a very small effect on the phospholipid diffusion. On the other hand, cholesterol has a great influence on the molecular ordering in the bilayer and on the lipid phase structure. It is therefore suggested that cholesterol exerts its dominant effect on the lipid membrane stability.