Acute effects of low-frequency electromagnetic fields on leukocyte-endothelial interactions in vivo.

摘要

BACKGROUND: To clarify the effect of extremely low frequency electromagnetic field (ELF-EMF) on the microcirculatory system, acute effects on leukocyte-endothelium interactions resulting from ELF-EMF exposure were examined with conscious BALB/c mice by means of a dorsal skinfold chamber. MATERIALS AND METHODS: The fluorescent dye, rhodamine 6G, was injected into the caudal vein to visualize leukocytes in vivo and to analyze leukocyte-endothelium interactions. Mice were exposed in vivo to 50 Hz linear sinusoidal wave EMF at magnetic flux densities of 3, 10 or 30 mT, for 30 minutes. RESULTS: The mean velocity of free flowing leukocytes in the center stream of venules revealed no distinct changes following exposure. However, at a flux density of 30 mT, the number of adherent leukocytes, defined as the total number of rolling and endothelium-adhering leukocytes, increased significantly following ELF-EMF exposure (p<0.05); no significant differences in adherent cell numbers were found in the 3 mT and 10 mT exposure groups or sham controls comparing pre- and post-exposure periods. CONCLUSION: These results demonstrated that high magnetic flux densities of ELF-EMF had an effect on leukocyte-endothelium interactions and indicated that a threshold level for this phenomenon exists in the range of 10-30 mT under these experimental conditions.