Nielsen H V, Staberg B, Nielsen K, Sejrsen P
Department of Medical Physiology B, University of Copenhagen, Denmark.
Acta Physiol Scand. 1988 Dec;134(4):513-8. doi: 10.1111/j.1748-1716.1998.tb08525.x.
Subcutaneous blood flow (SBF) was studied simultaneously in the upper arm at heart level and in the lower limb during positional changes and during leg exercise in seven healthy males. SBF was estimated by local clearance of 133Xenon registered by portable cadmium telluride detectors. Venous pressure was recorded directly on dorsum on the foot. Changing the position from supine to head-up tilt, SBF decreased by 43% (P less than 0.01) at the arm level, 40% at the thigh (P less than 0.01), 47% at the calf (P less than 0.01) and decreased by 51% at the ankle level (P less than 0.01). Performing 20 heel-raisings per min in nearly erect posture, SBF increased by 96% at the thigh (P less than 0.01), 25% at the calf (P greater than 0.1) and increased by 18% at the ankle level (P greater than 0.01). At 40 heel-raisings per min SBF increased by 99% at the thigh (P less than 0.01), 121% at the calf (P less than 0.01), but only 44% at the ankle level (P greater than 0.1). During leg exercise subcutaneous vascular resistance was significantly increased at arm and ankle levels. In contrast, a vasodilatory response was noticed at the thigh and calf levels and seemed associated with a decrease in local venous pressure to below the trigger level of the sympathetic veno-arteriolar reflex mechanism. In conclusion, SBF in the lower limb of man was increased during exercise. The increase in SBF could only partly be ascribed to the concomitant increase in perfusion pressure. The local blood flow response seemed modified by changes in sympathetic nervous activity and metabolic rate.
在七名健康男性中，研究了他们在体位改变和腿部运动期间，心脏水平上臂和下肢的皮下血流（SBF）情况。通过便携式碲化镉探测器记录的133氙的局部清除率来估计SBF。直接在足背记录静脉压。从仰卧位变为头高位倾斜时，上臂水平的SBF下降了43%（P<0.01），大腿处下降了40%（P<0.01），小腿处下降了47%（P<0.01），脚踝水平下降了51%（P<0.01）。以近乎直立的姿势每分钟进行20次提踵动作时，大腿处的SBF增加了96%（P<0.01），小腿处增加了25%（P>0.1），脚踝水平增加了18%（P>0.01）。每分钟进行40次提踵动作时，大腿处的SBF增加了99%（P<0.01），小腿处增加了121%（P<0.01），但脚踝水平仅增加了44%（P>0.1）。在腿部运动期间，上臂和脚踝水平的皮下血管阻力显著增加。相比之下，在大腿和小腿水平观察到血管舒张反应，这似乎与局部静脉压降至交感神经静脉-小动脉反射机制的触发水平以下有关。总之，人下肢的SBF在运动期间增加。SBF的增加只能部分归因于灌注压力的相应增加。局部血流反应似乎受到交感神经活动和代谢率变化的影响。
