蜘蛛香环烯醚萜对肠易激综合征模型大鼠胃肠敏感性和胃肠激素的影响

Influences of iridoid from Valeriana jatamansi Jones.on gastrointestinal sensitivity and hormones in rats with irritable bowel syndrome*

目的探讨蜘蛛香环烯醚萜治疗肠易激综合征(IBS)作用机理。方法雄性SD大鼠89只,分为空白组14只,模型组、氟西汀组和蜘蛛香环烯醚萜大(24.92 mg/kg)、中(12.46 mg/kg)、小(6.23 mg/kg)3个剂量组各15只。以慢性应激加孤养的方法造模,观察蜘蛛香环烯醚萜对腹部回撤反射(AWR)压力阈值和结肠P物质(SP)、血管活性肠肽(VIP)含量的影响。结果模型组大鼠疼痛压力阈值和最大耐受压力阈值均显著降低(P<0.01),蜘蛛香环烯醚萜3个剂量组AWR值都有显著改善,尤其是大、中剂量组效果极显著(P<0.001)。模型组结肠中SP有升高趋势,VIP有降低趋势,蜘蛛香环烯醚萜各剂量组均可降低SP,以大剂量组更为明显(P<0.01),并有升高VIP和降低结肠中SP/VIP值的趋势。结论蜘蛛香环烯醚萜对胃肠道功能亢进有明显抑制作用,可降低内脏敏感性,提示蜘蛛香环烯醚萜对肠易激综合征(IBS)的症状有改善作用,机制可能与可调节胃肠激素VIP、SP有关。

Objective To investigate the mechanism of iridoid from Valeriana jatamansi Jones. for treating irritable bowel syndrome. Method Male SD rats （n = 89） were randomly divided into the blank group （n=14）, model group （n = 15）, fluoxetine group （n = 15） and iridoid groups in three doses （24.92 mg/kg, 12.46 mg/kg, 6.23 mg/kg, each n = 15 ）. The model was established by chronic stress and independent feeding. The influences of iridoid from Valeriana jatamansi Jones. on the threshold of abdominal withdraw reflection （ AWR）, and the contents of substance P （SP） and vasoactive intestinal peptide （VIP） in the colon were observed in all groups. Result In the model group pain threshold and maximum tolerance pressure threshold reduced significantly （ P 〈 0.01 ）. In three iridoid groups AWR threshold was improved significantly, especially in the groups with the dose of 24.92 mg/kg and 12.46 mg/kg, and the improvement was greatly significant （P 〈0. 001 ）. In the model group SP content tended to elevation and VIP content tended to reduction. In the iridoid groups SP content decreased especially in the group with the dose of 24.92 mg/kg （P 〈0.01 ）, VIP content tended to elevation and the ratio of SP to VIP tended to reduction. Conclusion Iridoid from Valeriana jatamansi Jones. has a significant inhibitory effect on gastrointestinal hyperfunction. It can reduce the sensitivity of the internal organs, which indicates that it can relief the symptoms of irritable bowel syndrome. The mechanism may be related to that it can regulate the levels of gastrointestinal hormones （VIP and SP）.