Wilder-Smith Clive H, Robert-Yap Joan
Brain-Gut Research Group, Bubenbergplatz 11, CH-3011 Berne, Switzerland.
World J Gastroenterol. 2007 Jul 21;13(27):3699-704. doi: 10.3748/wjg.v13.i27.3699.
To investigate the role of endogenous pain modulatory mechanisms in the central sensitization implicated by the visceral hypersensitivity demonstrated in patients with irritable bowel syndrome (IBS). Dysfunction of modulatory mechanisms would be expected to also result in changes of somatic sensory function.
Endogenous pain modulatory mechanisms were assessed using heterotopic stimulation and somatic and visceral sensory testing in IBS. Pain intensities (visual analogue scale, VAS 0-100) during suprathreshold rectal distension with a barostat, cold pressor stimulation of the foot and during both stimuli simultaneously (heterotopic stimulation) were recorded in 40 female patients with IBS and 20 female healthy controls.
Rectal hypersensitivity (defined by 95% CI of controls) was seen in 21 (53%), somatic hypersensitivity in 22 (55%) and both rectal and somatic hypersensitivity in 14 of these IBS patients. Heterotopic stimulation decreased rectal pain intensity by 6 (-11 to -1) in controls, but increased rectal pain by 2 (-3 to +6) in all IBS patients (P < 0.05) and by 8 (-2 to +19) in IBS patients with somatic and visceral hypersensitivity (P < 0.02).
A majority of IBS patients had abnormal endogenous pain modulation and somatic hypersensitivity as evidence of central sensitization.
探讨内源性疼痛调节机制在肠易激综合征（IBS）患者内脏高敏感性所涉及的中枢敏化中的作用。调节机制功能障碍预计也会导致躯体感觉功能的改变。
在IBS患者中，采用异位刺激以及躯体和内脏感觉测试对内源性疼痛调节机制进行评估。记录40例女性IBS患者和20例女性健康对照者在使用恒压器进行阈上直肠扩张、足部冷加压刺激以及两种刺激同时进行（异位刺激）时的疼痛强度（视觉模拟评分，VAS 0 - 100）。
这些IBS患者中，21例（53%）出现直肠高敏感性（由对照者的95%置信区间定义），22例（55%）出现躯体高敏感性，14例同时出现直肠和躯体高敏感性。异位刺激使对照组直肠疼痛强度降低6（-11至-1），但使所有IBS患者的直肠疼痛增加2（-3至+6）（P < 0.05），使同时存在躯体和内脏高敏感性的IBS患者的直肠疼痛增加8（-2至+19）（P < 0.02）。
大多数IBS患者存在内源性疼痛调节异常和躯体高敏感性，作为中枢敏化的证据。
