Affiliations: [a] Department of Veterinary Surgery, Faculty of Veterinary Medicine, Hokkaido University, Japan | [b] Division of Physiology, Research Institute of Applied Electricity, Hokkaido University, Sapporo, 060, Japan
Note: [] Accepted by: Editor H. Niimi
Abstract: The membrane viscosity of peripheral blood lymphocytes (PBLs) of equine, bovine and canine was measured by the use of time-resolved fluorescence depolarization technique with 1,6-diphenyl-1,3,5-hexatriene(DPH). The viscosity values were 0.55, 0.59 and 0.50 poise for equine, bovine and canine PBLs, respectively. These values were compared with steady-state anisotropies and order parameters measured from electron spin resonance (ESR) of 5-doxyl stearic acid. Both values were increased with increase of viscosity. The fluid property of the membranes stimulated with phytohemagglutinin-P (PHA) was measured with steady-state fluorescence anisotropy and ESR. Little change of membrane fluidity was recognized with both methods during the stimulation with PHA. It appears that PHA activation process for these lymphocytes does not include large increase of the membrane fluidity which significantly accelerate the diffusion velocity of receptors in the plasma membrane.
