Affiliations: Division of Physiology, Research Institute of Applied Electricity, Hokkaido University, Sapporo, 060, Japan
Note: [] Accepted by: Editor E. Fukada
Abstract: The viscosity and the order in the interior of human erythrocyte membranes were investigated by the fluorescence depolarization technique in the nanosecond region with 1,6-diphenyl-1,3,5-hexatriene (DPH). After pulsed excitation with a polarized light, the fluorescence anisotropy ratio of DPH in membranes rapidly decreased and gave a final value (r∞). The rate of initial decrease and the value of r∞ related to the viscosity in the interior of the membranes and a wobbling angle of DPH which reflects a size of range for the phospholipid motion relating to the order of membrane structure. For normal human erythrocyte membranes the viscosity and the wobbling angle were obtained to be 0.82 poise and 42°, at 37°C. Similar values were obtained for spectrin-free membranes. Hardened membranes by the cross-linking of the cytoskeletal proteins with glutaraldehyde showed a small wobbling angle of 37°, but the viscosity of them was unchanged.
