Richardson D, Schwartz R, Hyde G
Microvasc Res. 1985 Jul;30(1):80-7. doi: 10.1016/0026-2862(85)90040-8.
The purpose of this study was to investigate reactive hyperemia in the capillary network of human skin in terms of the flow per capillary and the density of flow-active capillaries. Seventeen male subjects 20 to 40 years of age were seated with their right foot placed on the stage of a Leitz epi-ilumination microscope such that the nailfold capillary field in their large toes could be viewed. These vessels were video taped while flow velocity in the right posterior tibial artery was recorded via Doppler ultrasound at rest, then following a 45-sec period of arterial occlusion to the foot. Subsequent to experimentation flow velocity in single nailfold capillaries was measured via video densitometry and the number of flow-active capillaries in the field of view were counted. Following the release of arterial occlusion arterial flow velocity increased 142% above rest, the velocity in single capillaries increased by 54%, and the density of flow-active capillaries, as identified by the presence of red cells, decreased by 37%. The fact that capillary flow velocity increased to a lesser degree than arterial velocity during reactive hyperemia vis-a-vis a decrease in the number of flow-active capillaries indicates that ischemia to the foot elicits a smaller dilatory effect in vascular elements controlling blood flow to the superficial cutaneous region of the toe as compared to other regional vascular networks.
本研究的目的是从每根毛细血管的血流量和有血流活性的毛细血管密度方面，对人体皮肤毛细血管网中的反应性充血进行研究。17名年龄在20至40岁之间的男性受试者坐着，将右脚放在徕卡落射照明显微镜的载物台上，以便能够观察其大脚趾的甲襞毛细血管区域。在通过多普勒超声记录右胫后动脉在静息状态下的血流速度后，对这些血管进行录像，然后对足部进行45秒的动脉闭塞。实验后，通过视频密度测定法测量单个甲襞毛细血管中的血流速度，并计算视野中有血流活性的毛细血管数量。动脉闭塞解除后，动脉血流速度比静息时增加了142%，单个毛细血管中的血流速度增加了54%，而通过红细胞的存在确定的有血流活性的毛细血管密度降低了37%。与其他区域血管网络相比，在反应性充血期间毛细血管血流速度的增加程度小于动脉血流速度，同时有血流活性的毛细血管数量减少，这一事实表明，足部缺血对控制脚趾浅表皮肤区域血流的血管成分产生的扩张作用较小。
