Bergersen T K, Eriksen M, Walløe L
Department of Physiology, University of Oslo, Norway.
Am J Physiol. 1995 Aug;269(2 Pt 2):R325-30. doi: 10.1152/ajpregu.1995.269.2.R325.
The effect of local heating on blood velocities in arteries supplying the skin of hand and fingers was studied in subjects kept in their thermoneutral zone. The temperature of one hand was steadily raised from 35 to 43 degrees C in 15 min, whereas the control hand was kept in the air or immersed in a water bath at 35 degrees C. Simultaneous blood velocity recordings from the two hands were made continuously using ultrasound Doppler. In the heated hand, a general rise in blood velocity level was seen. However, the spontaneous fluctuations in blood velocity assumed to be caused by synchronous vasomotor activity of the arteriovenous anastomoses (AVAs) remained unchanged and closely correlated with those in the control hand throughout the experiment. Thus the central nervous control of AVA vasomotion seems to be unaffected by local heating. The elevation of blood velocity in the heated hand is probably due to dilatation of other parts of the vascular bed, e.g., ordinary arterioles in the skin. Earlier investigators, using venous occlusion plethysmography, have reported vasoconstriction in the locally heated human finger. No sign of such heat-induced vasoconstriction was found in this study.
在处于热中性区的受试者中，研究了局部加热对供应手部和手指皮肤的动脉中血流速度的影响。一只手的温度在15分钟内从35℃稳步升至43℃，而对照手则置于空气中或浸入35℃的水浴中。使用超声多普勒连续同步记录两只手的血流速度。在受热的手中，可见血流速度普遍升高。然而，假定由动静脉吻合支（AVAs）同步血管运动活动引起的血流速度自发波动保持不变，并且在整个实验过程中与对照手中的波动密切相关。因此，AVA血管运动的中枢神经控制似乎不受局部加热的影响。受热手中血流速度的升高可能是由于血管床其他部分的扩张，例如皮肤中的普通小动脉。早期研究人员使用静脉阻塞体积描记法报告了局部受热的人手指中的血管收缩。在本研究中未发现这种热诱导血管收缩的迹象。
