Drummond P D, Finch P M, Smythe G A
Psychology Section, Murdoch University, Western Australia.
Brain. 1991 Oct;114 ( Pt 5):2025-36. doi: 10.1093/brain/114.5.2025.
In 26 patients with features of reflex sympathetic dystrophy, venous blood was collected from painful and unaffected limbs. Levels of plasma adrenaline, noradrenaline and its intracellular metabolite, 3,4-dihydroxyphenylethyleneglycol (DHPG), were measured by combined gas chromatography/mass spectrometry. Plasma DHPG was lower on the painful side. Concentration of plasma noradrenaline was also lower on the painful side in patients with widespread allodynia, and in those with hyperhidrosis in the affected hand or foot. These findings do not support the widely held view that autonomic disturbances in reflex sympathetic dystrophy are due to sympathetic overactivity. Rather, they suggest that sweating and changes in peripheral blood flow result from supersensitivity to sympathetic neurotransmitters. After injury, supersensitivity to noradrenaline may also contribute to spontaneous pain and allodynia by disrupting efferent sympathetic modulation of sensation. This would explain why pain and allodynia are relieved by sympathetic blockade, and why noradrenaline rekindles pain in sympathectomized skin.
在26例具有反射性交感神经营养不良特征的患者中，从疼痛肢体和未受影响的肢体采集静脉血。通过气相色谱/质谱联用技术测定血浆肾上腺素、去甲肾上腺素及其细胞内代谢产物3,4-二羟基苯乙二醇（DHPG）的水平。疼痛侧的血浆DHPG较低。在广泛存在痛觉过敏的患者以及患手或患足有多汗症的患者中，疼痛侧的血浆去甲肾上腺素浓度也较低。这些发现不支持广泛持有的观点，即反射性交感神经营养不良中的自主神经紊乱是由于交感神经过度活跃所致。相反，它们表明出汗和外周血流变化是对交感神经递质超敏反应的结果。损伤后，对去甲肾上腺素的超敏反应也可能通过破坏传出交感神经对感觉的调节而导致自发痛和痛觉过敏。这就解释了为什么交感神经阻滞能缓解疼痛和痛觉过敏，以及为什么去甲肾上腺素会在交感神经切除的皮肤中引发疼痛。
