脾虚湿困型溃疡性结肠炎大鼠模型的建立与评价

目的：建立符合中医证候特点的脾虚湿困型溃疡性结肠炎（ulcerativecolitis,UC）大鼠模型。方法：60只大鼠随机分为正常对照组、三硝基苯磺酸（trinitrobenzenesulfonicacid,TNBS）模型组,内外因加TNBS模型组及健脾化湿防治组。正常对照组给予普通喂养;TNBS模型组采用TNBS与乙醇复合物进行造模,内外因加TNBS模型组大鼠给予环境与饮食因素干预结合TNBS与乙醇复合物进行造模,健脾化湿防治组在内外因加TNBS模型复制过程中给予参苓白术散煎剂灌胃。观察各组大鼠症状、体征、病理改变,并检测血清白细胞介素6（interleukin-6,IL-6）、白细胞介素8（interleukin-8,IL-8）及肿瘤坏死因子a（tumornecrosisfactor-α,TNF-α）的浓度。结果：内外因加TNBS模型组大鼠出现嗜睡懒动、蜷缩,饮少纳呆,精神萎靡,毛发疏松粗糙、晦暗无光泽,腹泻及黏液血便症状;大鼠体质量明显下降,摄食饮水量明显降低,小便量明显减少,大便湿重增加,自发活动次数明显减少,与正常对照组比较差异有统计学意义（P〈0．05）;镜下观察黏膜见水肿、充血、大量炎症细胞浸润,伴有溃疡灶形成;大鼠结肠组织损伤程度评分及IL-6、IL-8和TNF-α的浓度与正常对照组比较,差异有统计学意义（P〈0．01）。健脾化湿防治组大鼠经治疗后体质量明显增加,摄食饮水量明显增多,小便量明显增加,大便湿重减少,自发活动次数明显增多,与TNBS模型组及内外因加TNBS模型组比较,差异有统计学意义（P〈0．05）;结肠黏膜见轻度充血、水肿,仅有少量炎性细胞浸润,其结肠组织损伤程度评分及IL-6、IL-8和TNF-α的浓度与内外因加TNBS模型组比较差异均有统计学意义（P〈0．05）。结论：环境与饮食因素干预结合TNBS与乙醇复合物建立的脾虚湿困型UC大鼠模型,符合人类自然发生的UC病变特点和中医证候特点,是较理想的脾虚湿困型UC模型。

Establishment and evaluation of a rat model of ulcerative colitis with syndrome of dampness stagnancy due to spleen deficiency

OBJECTIVE： To establish a rat model of ulcerative colitis with syndrome of spleen deficiency and dampness stagnancy. METHODS： Sixty rats were divided into normal control group, ulcerative colitis group, ulcerative colitis with syndrome of spleen deficiency and dampness stagnancy group （model group） and strengthening spleen for resolving dampness group. Ulcerative colitis in rats was induced by enema containing trinitrobenzene sulfonic acid （TNBS） and ethanol. The rats in the model group were suffered from standing in water, limiting sleeping time and abnormal diet based on administration of TNBS and ethanol. The rats in the spleen strengthening and dampness resolving group were gastrically administered with Shenlin Baizhu Powder, a compound traditional Chinese herbal medicine. Symptoms, signs and pathological changes in colon tissue of rats were observed after modeling. The levels of interleukin （IL）-6, IL-8 and tumor necrosis factor-~ （TNF-a） in serum of rats were measured by enzyme-linked immunosorbent assay. RESULTS： The rats in the model group showed lethargy, poor appetite, loss of energy, diarrhea and bloody stool. Their body weight decreased significantly compared with the normal control group, and similar changes were found in the comparison of food intake, drinking amount, urine amount, stool wet weight and assay of spontaneous activity （P〈0.05）. When observed under a light microscope, the colon tissues of rats in the model group showed mucosal edema, congestion, inflammatory cell infiltration and ulceration. The degree of colon injury and IL-6, IL-8 and TNF-α levels were significantly increased （P〈0.05） as compared to those in the normal control group. The changes mentioned above were improved by Shenlin Baizhu Powder （P〈0.05）. CONCLUSION： The rat model of ulcerative colitis with syndrome of spleen deficiency and dampness stagnancy is successfully induced and has the characteristics of ulcerative colitis of humans both in pathological changes and in syndrome.