Koyama T, Zhu M Y, Araiso T, Kinjo M, Kitagawa H, Sugimura M
Physiology Section, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
Jpn J Physiol. 1990;40(1):65-78. doi: 10.2170/jjphysiol.40.65.
The viscosity of the phospholipid bilayer and the wobbling angle of the phospholipid molecules of mitochondrial membranes and plasma membranes from bullfrog myocardium were measured with a nanosecond time-resolved fluorometer using pulsed excitation of a hydrophobic fluorescent probe, 1,6-diphenyl-1,3,5-hexatriene (DPH). The mean +/- S.D. in the viscosity of the mitochondrial and plasma membranes was 0.54 +/- 0.9 and 0.37 +/- 0.03 P, respectively, at 30 degrees C. The wobbling angle of phospholipid molecules was 42 +/- 1 and 47 +/- 1 degree, respectively. Cholesterol content was lower in mitochondria (6.4 micrograms/mg protein) than in plasma membranes (43.7 micrograms/mg protein) but phosphatidylethanolamine concentration was higher in mitochondria (31.8%) than in plasma membranes (27.3%). Cardiolipin was contained only in mitochondria. The results of these lipid analyses appear consistent with the measurements of membrane viscosity and phospholipid wobbling angle. When the results are compared with those from a previous study on the erythrocyte membranes from bullfrogs, viscosity is found to increase in the order mitochondrial membranes less than plasma membranes less than erythrocyte membranes. The complex requirements of biomembranes of organelles performing different functions appear to be met by the particular dynamic microstructure of the biomembrane. The effect of membrane viscosity on oxygen diffusion through membranes is discussed.
使用疏水性荧光探针1,6 - 二苯基 - 1,3,5 - 己三烯（DPH）的脉冲激发，通过纳秒时间分辨荧光计测量了牛蛙心肌线粒体膜和质膜的磷脂双分子层粘度以及磷脂分子的摆动角度。在30℃时，线粒体膜和质膜粘度的平均值±标准差分别为0.54±0.09和0.37±0.03泊。磷脂分子的摆动角度分别为42±1度和47±1度。线粒体中的胆固醇含量（6.4微克/毫克蛋白质）低于质膜（43.7微克/毫克蛋白质），但线粒体中磷脂酰乙醇胺的浓度（31.8%）高于质膜（27.3%）。心磷脂仅存在于线粒体中。这些脂质分析结果似乎与膜粘度和磷脂摆动角度的测量结果一致。当将这些结果与先前关于牛蛙红细胞膜的研究结果进行比较时，发现粘度按线粒体膜＜质膜＜红细胞膜的顺序增加。执行不同功能的细胞器生物膜的复杂需求似乎通过生物膜特定的动态微观结构得到满足。本文还讨论了膜粘度对氧气通过膜扩散的影响。
