Kurvers H A, Tangelder G J, De Mey J G, Slaaf D W, Beuk R J, van den Wildenberg F A, Kitslaar P J, Reneman R S, Jacobs M J
Department of General Surgery, University Hospital Maastricht, The Netherlands.
J Auton Nerv Syst. 1997 Mar 19;63(1-2):19-29. doi: 10.1016/s0165-1838(96)00127-0.
Loose ligation of a sciatic nerve in rats provokes signs and symptoms like those observed in human conditions of neuropathic pain. Some of these have been associated with sympathetic dysfunction. Since the skin microcirculation in the rat is strongly influenced by sympathetic tone, abnormalities in skin blood flow may be used as an indirect measure of sympathetic dysfunction. We measured, by means of laser Doppler flowmetry, skin blood flow at the plantar surface of the rat hind paw before and after ipsilateral loose sciatic nerve ligation. We assessed basal skin blood flow as well as the vasoconstrictor response which follows cooling of the rat abdomen. The effectiveness of this response may be used as a measure of sympathetic vasoconstrictor outflow. As compared to the values obtained before ligation (= 100%): (1) the vasoconstrictor response was impaired (65%, P < 0.01) from day 1 onwards, whereas (2) basal skin blood flow was increased (171%; P < 0.01) from day 3 until day 5, and decreased (51%, P < 0.0001) from day 7 until day 28. At day 28, blockade of impulse propagation in the loosely ligated sciatic nerve (by means of lidocaine) did not increase the lowered level of skin blood flow. These findings suggest that in the chronic construction injury model loose ligation of a sciatic nerve reduces sympathetic vasoconstrictor outflow, which, in turn may induce supersensitivity of skin microvessels to catecholamines.
在大鼠中对坐骨神经进行松结扎会引发类似于人类神经性疼痛状况中所观察到的体征和症状。其中一些与交感神经功能障碍有关。由于大鼠的皮肤微循环受交感神经张力的强烈影响，皮肤血流异常可被用作交感神经功能障碍的间接指标。我们通过激光多普勒血流仪测量了同侧坐骨神经松结扎前后大鼠后爪足底表面的皮肤血流。我们评估了基础皮肤血流以及大鼠腹部冷却后的血管收缩反应。这种反应的有效性可被用作交感神经血管收缩流出的指标。与结扎前获得的值（=100%）相比：（1）从第1天起血管收缩反应受损（65%，P<0.01），而（2）基础皮肤血流从第3天到第5天增加（171%；P<0.01），从第7天到第28天减少（51%，P<0.0001）。在第28天，在松结扎的坐骨神经中阻断冲动传导（通过利多卡因）并未增加降低的皮肤血流水平。这些发现表明，在慢性构建损伤模型中，坐骨神经的松结扎会减少交感神经血管收缩流出，这反过来可能会诱导皮肤微血管对儿茶酚胺超敏。
