Fechir M, Schlereth T, Kritzmann S, Balon S, Pfeifer N, Geber C, Breimhorst M, Eberle T, Gamer M, Birklein F
Department of Neurology, Johannes Gutenberg-University Mainz, Mainz, Germany.
Eur J Pain. 2009 Oct;13(9):935-41. doi: 10.1016/j.ejpain.2008.11.002. Epub 2009 Jan 10.
Stress and thermoregulation both activate the sympathetic nervous system (SNS) but might differently affect pain. Studies investigating possible interactions in patients are problematic because of the high prevalence of SNS disturbances in patients. We therefore analyzed the influence of these different sympathetic challenges on experimentally-induced pain in healthy subjects. SNS was activated in two different ways: by mental stress (Stroop task, mental arithmetic task), and by thermoregulatory stimulation using a water-perfused thermal suit (7 degrees C, 32 degrees C, or 50 degrees C). Attentional effects of the mental stress tasks were controlled by using easy control tasks. Both, stress and thermoregulatory stimuli, robustly activated SNS parameters. However, the patterns of activation were different. While stress co-activated heart rate, blood pressure, peripheral vasoconstriction and sweating, thermal stimulation either increased blood pressure (cold) or heart rate and sweating (warm). Only stress was able to induce a significant reduction of pain. The control tasks neither activated the SNS nor altered pain perception. Our results suggest that (1) different patterns of sympathetic activation can be recorded after stress and thermoregulatory challenges and (2) that only stress is able to interfere with sensation of experimental pain. Whether SNS activation is causally responsible for analgesia needs to be further investigated.
压力和体温调节都会激活交感神经系统（SNS），但可能对疼痛产生不同的影响。由于患者中SNS紊乱的高患病率，研究患者中可能的相互作用存在问题。因此，我们分析了这些不同的交感神经刺激对健康受试者实验性疼痛的影响。SNS通过两种不同的方式被激活：通过精神压力（斯特鲁普任务、心算任务），以及通过使用水灌注热服（7摄氏度、32摄氏度或50摄氏度）进行体温调节刺激。通过使用简单的对照任务来控制精神压力任务的注意力效应。压力和体温调节刺激均有力地激活了SNS参数。然而，激活模式不同。压力同时激活心率、血压、外周血管收缩和出汗，而热刺激要么升高血压（冷刺激），要么升高心率和出汗（热刺激）。只有压力能够显著减轻疼痛。对照任务既未激活SNS，也未改变疼痛感知。我们的结果表明：（1）在压力和体温调节刺激后，可以记录到不同的交感神经激活模式；（2）只有压力能够干扰实验性疼痛的感觉。SNS激活是否是镇痛的因果原因需要进一步研究。
