Department of Psychology, The University of Tulsa, OK 74104, USA.
Ann Behav Med. 2012 Jun;43(3):343-51. doi: 10.1007/s12160-012-9345-x.
The menstrual cycle influences pain, with symptoms often increasing during the premenstrual (late-luteal) phase. Deficiencies in endogenous inhibition of afferent nociception at the spinal level might contribute to menstrual phase-related changes in pain.
This study assessed whether conditioned pain modulation (CPM) of spinal nociception differs between mid-follicular and late-luteal phases.
CPM was evoked by a blood pressure cuff affixed to the right forearm and inflated to induce ischemia in 41 healthy women during both menstrual phases. Suprathreshold electric stimuli were delivered to the left sural nerve to evoke pain and the nociceptive flexion reflex (NFR) before, during, and after forearm ischemia.
Forearm ischemia produced CPM of electrocutaneous pain and NFR, but inhibition did not differ across mid-follicular and late-luteal phases.
Mechanisms contributing to changes in experimental pain across mid-follicular and late-luteal phases in healthy women are not due to deficits in CPM of spinal nociception.
月经周期会影响疼痛，症状通常在经前期（黄体晚期）加重。脊髓水平传入伤害性感受的内源性抑制不足可能导致与月经周期相关的疼痛变化。
本研究评估在卵泡中期和黄体晚期，脊髓伤害性感受的条件性疼痛调制（CPM）是否存在差异。
在卵泡中期和黄体晚期，将血压袖带固定在右前臂并充气，以诱导 41 名健康女性右前臂缺血，从而诱发 CPM。在左腓浅神经上给予超阈值电刺激以诱发疼痛和伤害性屈肌反射（NFR），并在右前臂缺血前、缺血期间和缺血后进行测量。
右前臂缺血产生了对电皮肤痛和 NFR 的 CPM，但在卵泡中期和黄体晚期之间，抑制作用没有差异。
在健康女性中，卵泡中期和黄体晚期实验性疼痛变化的机制并非归因于脊髓伤害性感受 CPM 的缺陷。
