金荞麦片对脾虚湿热证腹泻型肠易激综合征大鼠免疫炎症和内脏高敏感性的影响

目的:研究金荞麦片对脾虚湿热证肠易激综合征腹泻型(diarrhea-predominant irritable bowel syndrome,IBS-D)大鼠免疫炎症和内脏高敏感性的影响.方法:选取SPF级新生SD大鼠,采用高乳糖饲料+慢性束缚+夹尾刺激诱导IBS-D大鼠模型.造模成功后,将实验动将物随机分为正常对照组(A组)、模型对照组(B组)、金荞麦片高剂量组(C组)、中剂量组(D组)、低剂量组(E组)、谷参肠安组(F组),金荞麦片组分别给予高剂量[6 g/(kg·d)]、中剂量[3 g/(kg·d)]和低剂量[1.5 g/(kg·d)]中药灌胃,谷参肠安组给予谷参肠安2 g/(kg·d),正常组和模型组分别给予等容积生理盐水灌胃,1次/d.灌胃4 wk后,行直肠内球囊扩张实验(colorectal distention,CRD),观察腹肌收缩反射(abdominal withdrawal reflex,AWR),评估大鼠结肠转运和感觉功能,放射免疫法检测血清肿瘤坏死因子-(tumor necrosis factor-,TNF-)、白介素-17(interleukin 17,IL-17)、IL-10、P物质(substance P,SP)和降钙素基因相关肽(calcitonin gene-related peptide,CGRP)含量,荧光定量PCR检测肠组织5-羟色胺(5-hydroxytryptamine,5-HT)、5-羟色胺3受体(5-hydroxytryptamine 3 receptor,5-HT3R)、神经激肽受体-1(neurokinin receptor 1,NK1R)和细胞间黏附分子(intracellular adhesion molecule-1,ICAM-1)mRNA表达水平.结果:与模型组比较,金荞麦片各剂量组大鼠结肠转运功能及内脏高敏感性明显降低(P<0.05或0.01),大鼠血清TNF-(2.81 ng/L±0.67 ng/L,2.76 ng/L±0.31 ng/L,2.91 ng/L±0.77 ng/L vs 3.77 ng/L±0.44 ng/L)、IL-17(2.01 ng/L±0.76 ng/L,2.14 ng/L±0.29ng/L,1.98 ng/L±0.11 ng/L vs 2.47 ng/L±0.33 ng/L)及SP(38.22 pg/mL±3.15 pg/mL,37.55 pg/mL±2.63 pg/mL,42.01 pg/mL±3.79pg/mL vs 43.19 pg/mL±4.28 pg/mL)含量均较模型组降低.IL-10(137.25 ng/L±6.2 ng/L,135.90 ng/L±4.4 ng/L,121.70 ng/L±5.11 ng/L vs 82.09 ng/L±5.33 ng/L)和CGRP(155.09 ng/L±4.38 ng/L,142.02 ng/L±2.44 ng/L,158.25ng/L±4.02 ng/L vs 107.31 ng/L±3.96 ng/L)明显升高(P<0.05或0.01).肠组织5-HT(0.74±0.43,0.97±0.91,0.66±0.29 vs 1.27±0.45)、5-HT3R(1.01±0.35,1.14±0.76,1.47±0.65 vs1.61±0.03)、NK1R(1.07±0.58,0.98±0.67,0.88±0.79 vs 1.47±0.94)和ICAM-1(0.81±0.55,0.96±0.19,0.72±0.93 vs 1.33±0.26)mRNA表达水平下调(P<0.05或0.01),尤以金荞麦片高剂量组为优.结论:金荞麦片可降低IBS-D大鼠内脏高敏感性,有效抑制免疫炎症反应,多靶点、多层次地参与调节胃肠动力.金荞麦片对实验性IBS-D具有量效依赖作用.