Department of Clinical Medicine, Federal University of Ceará, Brazil.
Aliment Pharmacol Ther. 2012 Mar;35(5):577-86. doi: 10.1111/j.1365-2036.2011.04977.x. Epub 2012 Jan 10.
Visceral tone supposedly affects gut sensitivity in irritable bowel syndrome (IBS). Sildenafil increases nitric oxide and influences visceral compliance.
To evaluate the effects of sildenafil tone inhibition on rectal sensitivity.
Eight controls and 21 IBS patients (Rome II) were enrolled in a double-blind study, after dosing with placebo or sildenafil (50 mg p.o.). Thresholds for first sensation, first desire to defecate, pain and supraliminar pain were the sensory endpoints, measured with a barostat and 600-mL rectal bag. Pain (100-mm VAS) and depression-anxiety (Hamilton questionnaire) were scored.
Irritable bowel syndrome rectal compliance and sensory-endpoint thresholds were similar to controls. Five IBS patients had pain threshold lower than controls 95% confidence interval (hypersensitive). Depression score was greater in IBS than controls (11.9 ± 1.3 vs. 6.3 ± 2.5, P = 0.036). In IBS, pain intensity was nonsignificantly higher (37.6 ± 5.3 mm vs. 23.4 ± 8.5 mm, P = 0.064) and supraliminar pain intensity was greater (45.6 ± 5.4 mm vs. 25.9 ± 5.1 mm, P = 0.044) than controls. IBS rectal relaxation increased volume (155.4 ± 41.3 mL vs. 118.8 ± 47.7 mL, P = 0.004) and tension (193.1 ± 118.6 mmHg mL(-1) vs. 133.2 ± 98.1 mmHg mL(-1) , P = 0.019) for triggering first desire to defecate but not for other perceptions. Sildenafil increased volume for both first desire to defecate and pain in the hypersensitive IBS patients. Sildenafil increased rectal compliance only in diarrhoea-IBS. Mixed-IBS obtained higher anxiety (12.9 ± 1.3 vs. 5.9 ± 3.1, P < 0.05) and depression scores (13.9 ± 1.9 vs. 6.3 ± 2.5, P < 0.05) and reported more intense supraliminar pain (53.6 ± 9.8 mm vs. 25.9 ± 5.1 mm, P < 0.05) than controls.
Rectal relaxation following dosing with sildenafil 50 mg increased the first desire to defecate threshold in IBS as a whole, but decreased pain only in the hypersensitive subset. Mixed-IBS presented higher supraliminar pain and anxiety-depression scores.
内脏张力据称会影响肠易激综合征（IBS）患者的肠道敏感性。西地那非可以增加一氧化氮并影响内脏顺应性。
评估西地那非抑制内脏张力对直肠敏感性的影响。
8 名对照者和 21 名 IBS 患者（罗马 II 标准）参与了这项双盲研究，他们接受了安慰剂或西地那非（50mg 口服）治疗。首次感觉、首次排便欲望、疼痛和超感觉疼痛的阈值是通过测压计和 600ml 直肠袋测量的感觉终点。疼痛（100mm VAS）和抑郁焦虑（汉密尔顿问卷）评分。
IBS 直肠顺应性和感觉终点阈值与对照组相似。5 名 IBS 患者的疼痛阈值低于对照组 95%置信区间（超敏）。IBS 患者的抑郁评分高于对照组（11.9 ± 1.3 vs. 6.3 ± 2.5，P = 0.036）。在 IBS 患者中，疼痛强度显著升高（37.6 ± 5.3mm vs. 23.4 ± 8.5mm，P = 0.064），超感觉疼痛强度更大（45.6 ± 5.4mm vs. 25.9 ± 5.1mm，P = 0.044）。IBS 直肠松弛增加了触发排便欲望的容量（155.4 ± 41.3ml vs. 118.8 ± 47.7ml，P = 0.004）和张力（193.1 ± 118.6mmHg mL-1 vs. 133.2 ± 98.1mmHg mL-1，P = 0.019），但对其他感觉无影响。西地那非增加了超敏 IBS 患者的排便欲望和疼痛的容量。西地那非仅增加了腹泻型 IBS 的直肠顺应性。混合 IBS 患者获得了更高的焦虑（12.9 ± 1.3 vs. 5.9 ± 3.1，P < 0.05）和抑郁评分（13.9 ± 1.9 vs. 6.3 ± 2.5，P < 0.05），并报告了更强烈的超感觉疼痛（53.6 ± 9.8mm vs. 25.9 ± 5.1mm，P < 0.05）。
IBS 患者口服西地那非 50mg 后直肠松弛增加了排便欲望的阈值，但仅在超敏亚组中降低了疼痛。混合 IBS 患者的超感觉疼痛和焦虑抑郁评分更高。
