艾灸对IBS-D模型大鼠海马与结肠组织中TNF-α表达的影响

Effect of Moxibustion on the Expression of TNF-αin Hippocampus and Colonic Tissues in IBS-D Model Rats

目的观察艾灸对腹泻型肠易激综合征(IBS-D)模型大鼠海马与结肠组织中肿瘤坏死因子(TNF)-α蛋白和mRNA表达的影响,探讨艾灸治疗IBS-D的机制。方法24只健康SD雄性大鼠随机分为空白组、模型组和艾灸组,每组8只。采用慢性束缚联合番泻叶灌胃方法建立IBS-D大鼠模型。艾灸组以艾灸天枢、上巨虚,治疗7d。治疗后观察大鼠稀便率和直肠扩张(CRD)所引起腹部回缩反射的最小容量阈值;采用免疫组化法检测海马和结肠组织中TNF-α蛋白表达;采用实时荧光定量PCR(RT-qPCR)法检测海马和结肠组织中TNF-αmRNA相对表达量,并通过Person相关系数分析两者相关性。结果与空白组比较,模型组海马和结肠组织中TNF-α蛋白和mRNA表达明显增加(P<0.01);与模型组比较,艾灸组海马和结肠组织中TNF-α蛋白和mRNA表达显著降低(P<0.01);Person分析结果显示,空白组、模型组和艾灸组海马与结肠组织中的TNF-α蛋白和mRNA表达量呈正相关(P<0.05)。结论艾灸天枢、上巨虚改善IBS-D大鼠腹泻症状和内脏高敏感性,可能与艾灸抑制海马和结肠组织中细胞因子TNF-α的表达,调节肠道黏膜免疫功能有关。

Objective To observe the effect of moxibustion on the protein and mRNA expressions of tumor necrosis factor(TNF)-αin hippocampus and colonic tissues in model rats with diarrhea-dominant irritable bowel syndrome(IBS-D),and to discuss the mechanism of moxibustion in treati ng IBS-D.Method Atotal of 24 healthy Sprague-Dawley(SD)rats were randomized into a blank group,a model group and a moxibustion group,with 8 rats in each group.The IBS-D rat model was established by chronic restraint combined with intragastric administration of Fan Xie Ye(Folium Sennae).The moxibustion group received moxibustion at Tianshu(ST25)and Shangjuxu(ST37)for 7 d.After intervention,the loose stool rate and the minimum volume threshold of colorectal distension(CRD)causing abdominal withdrawal reflex were observed;the protein expression of TNF-αin hippocampus and colonic tissues was detected using immunohistochemical method;the relative expression of TNF-αmRNA in hippocampus and colonic tissues was determined using real-time fluorescence quantitative PCR;Pearson correlation coefficient was used to analyze the correlation between the two expressions.Result Compared with the blank group,the protein and mRNA expressions of TNF-αin hippocampus and colonic tissues increased significantly in the model group(P<0.01);compared with the model group,the protein and mRNA expressions of TNF-αin hippocampus and colonic tissues decreased significantly in the moxibustion group(P<0.01);the Pearson analysis result showed that the protein and mRNA expressions of TNF-αin hippocampus were positively correlated with those in colonic tissues in the blank group,model group and moxibustion group(P<0.05).Conclusion Moxibustion at Tianshu(ST25)and Shangjuxu(ST37)can improve the diarrhea symptom and visceral hypersensitivity in IBS-D rats,which may be associated with its regulation of the intestinal mucosal immune function via inhibiting the expression of TNF-αin hippocampus and colonic tissues.