Kuiken S D, Klooker T K, Tytgat G N, Lei A, Boeckxstaens G E
Department of Gastroenterology and Hepatology, Academic Medical Centre, Amsterdam, The Netherlands.
Neurogastroenterol Motil. 2006 Feb;18(2):115-22. doi: 10.1111/j.1365-2982.2005.00731.x.
Visceral hypersensitivity is a consistent finding in a considerable proportion of patients with irritable bowel syndrome (IBS), and may provide a physiological basis for the development of IBS symptoms. In this study, we aimed to confirm the hypothesis that nitric oxide (NO) is involved in maintaining visceral hypersensitivity in IBS. Ten healthy volunteers (HV) and 12 IBS patients with documented hypersensitivity to rectal distension underwent a rectal barostat study. The effect of placebo and the specific NO synthase inhibitor NG -monomethyl-L-arginine (L-NMMA) on resting volume, rectal sensitivity to distension and rectal compliance was evaluated in a double-blind, randomized, cross-over fashion. NG -monomethyl-L-arginine did not alter resting volumes in HV or IBS patients. In HV, l-NMMA did not alter rectal sensory thresholds compared to placebo (45 +/- 3 and 46 +/- 3 mmHg, respectively). In contrast, L-NMMA significantly increased the threshold for discomfort/pain in IBS patients (placebo: 18 +/- 2, l-NMMA: 21 +/- 3 mmHg, P < 0.05). Rectal compliance was not affected by L-NMMA. Although NO does not seem to play a major role in normal rectal sensation or tone, we provide evidence that NO may be involved in the pathophysiology of visceral hypersensitivity in IBS.
内脏高敏感性在相当比例的肠易激综合征（IBS）患者中是一个持续存在的现象，并且可能为IBS症状的发展提供生理基础。在本研究中，我们旨在证实一氧化氮（NO）参与维持IBS内脏高敏感性这一假说。10名健康志愿者（HV）和12名记录显示对直肠扩张敏感的IBS患者接受了直肠压力测定研究。以双盲、随机、交叉方式评估安慰剂和特异性一氧化氮合酶抑制剂N-甲基-L-精氨酸（L-NMMA）对静息容量、直肠对扩张的敏感性和直肠顺应性的影响。N-甲基-L-精氨酸未改变HV或IBS患者的静息容量。在HV中，与安慰剂相比，L-NMMA未改变直肠感觉阈值（分别为45±3和46±3 mmHg）。相比之下，L-NMMA显著提高了IBS患者不适/疼痛的阈值（安慰剂：18±2，L-NMMA：21±3 mmHg，P<0.05）。直肠顺应性不受L-NMMA影响。虽然NO似乎在正常直肠感觉或张力中不发挥主要作用，但我们提供证据表明NO可能参与IBS内脏高敏感性的病理生理学过程。
