结肠灵汤对肠易激综合征大鼠肠组织及脊髓后角脑肠肽表达的影响

Effects of Jiechangling decoction on the expressions of braingut petide in intestine and posterior horn of spinal cord in the rat model of irritable bowel syndrome

目的探讨结肠灵汤对肠易激综合征大鼠肠黏膜及脊髓后角P物质(SP)、血管活性肠肽(VIP)阳性神经纤维表达的影响。方法将实验动物分为对照组、模型组、西药组及中药低、高剂量组。采用结肠慢性刺激法制作肠道高敏性大鼠模型,观察各组大鼠肠道敏感性指标,用免疫组织化学法对各组大鼠回盲部、结肠及脊髓后角SP、VIP的表达进行半定量分析。结果各治疗组大鼠肠道敏感性指标均有明显改善,结肠灵汤能降低大鼠肠组织SP、VIP的免疫表达及脊髓后角SP的免疫表达,呈一定量效关系。结论结肠灵汤可改善肠道敏感性症状,其机制可能在于调节肠道初级感觉神经纤维SP、VIP的分泌,抑制伤害性初级传入末梢上行释放SP,减弱背角神经兴奋性,从而提高内脏痛阈,改善腹痛腹泻症状。

Objective It is to explore the effect of Jiechangling decoction on the positive expression of substance P （SP） and vasoactive intestinal peptide （VIP） in intestine and posterior horn of spinal cord in the rat model of irritable bowel syndrome （IBS）. Methods The visceral hypersensitivity rats were induced by chronic stress excitation on colon, then the experimental animals were randomly divided into control group, model group, western medicine group and groups of high and low dosage of Jiechangling decoction. The indexes of intestine sensitivity in each group were observed. The expressions of SP and VIP in ileocecal junction tissue, colon tissue and posterior horn of spinal cord were analyzed semi-quantitatively with immunohistochemistry method. Results Sensitive indexes of intestines in every treatment group were all improved obviously. Jiechangling decoction could decrease the expressions of SP and VIP in intestine tissue and SP in posterior horn of spinal cord, and its effect depended on the dose of Jiechangling decoction. Conclusion Jiechangling decoction can improve the symptoms of intestine sensitivity. Its mechanism may be that it can adjust to the secretion of SP and VIP in intestinal primary sensory nerve fibre, and inhibit the delivery of SP from primary nocuity afferent fiber, reduce the excitability of DRG and increase visceral pain threshold, in order to cure abdominal pain and diarrhea.