IWASE Satoshi Nagoya University, Research Institute of Environmental Medicine, Associate Professor, 環境医学研究所, 助教授 (90184879)
MANO Tadaaki Nagoya University, Research Institute of Environmental Medicine, Professor, 環境医学研究所, 教授 (30023659)
|Budget Amount *help
¥3,000,000 (Direct Cost: ¥3,000,000)
Fiscal Year 2000: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1999: ¥2,400,000 (Direct Cost: ¥2,400,000)
To analyze how the one-minute oscillation in muscular blood flow in the lower legs relates to one-minute wave in body fluid volume change during upright standing in humans, blood flow and blood pressure in the leg, oxygen saturation level of the blood and hemoglobin volume in the tissue of the calf muscle, heart rate, stroke volume, cardiac output, peripheral blood pressure at heart level, 14 levels of body circumference, volumes of the leg, abdomen and thorax, electromyograms, foot pressure center were measured during upright standing for 40 min in 11 healthy young men. Spectral analyzes of these parameters revealed that the one-minute rhythm is found in all parameters. One-minute wave in body fluid volume change in the lower legs, which occurred in fluid pooling caused by gravity, propagated upward. Muscle pumping in the lower legs triggered by the postural sway was found to increase the power of one-minute wave. Phase analysis of one-minute oscillation revealed that the increase phase in volume of the leg, the one in the blood flow in the leg, the one in the hemoglobin volume in the tissue, elevating phase of blood pressure in the leg, and the one in oxygen saturation level of the blood were reasonably within the early phase of one-minute oscillation. The one-minute oscillation in the oxygen saturation level of the blood and the hemoglobin volume in the tissue were very clear. These results suggest that the origin of one-minute wave in body fluid volume change exists in the blood circulatory system, not in the lymph system. We conclude that the origin of one-minute wave in body fluid volume change is spontaneous constriction of peripheral blood vessels triggered by an elevation of transmural pressure when the pooling is generated.