葡聚糖硫酸钠自由饮用与定量灌胃诱导小鼠急性结肠炎模型的比较研究

背景：自由饮用葡聚糖硫酸钠（DSS）诱导的鼠类急性结肠炎模型均一性欠佳,动物死亡率较高。目的：评估2%DSS自由饮用或定量灌胃诱导的小鼠急性结肠炎模型模拟人类溃疡性结肠炎（UC）的效果和均一性。方法：予ICR小鼠2%DSS自由饮用或定量灌胃建立急性结肠炎模型,检测并比较正常对照组和两组模型小鼠的症状出现时间和频率、疾病活动指数（DAI）、DSS消耗量、死亡率、结肠长度、结肠损伤大体评分（MACD）、结肠组织病理学表现以及外周血白细胞计数和分类。结果：两组模型小鼠均出现类似人类UC的症状和组织病理学改变,结肠显著短缩,DAI、MACD以及外周血白细胞计数和中性粒细胞百分比显著高于正常对照组。与DSS自由饮用组相比,DSS定量灌胃组小鼠症状出现时间更为一致,症状出现率显著增高,动物死亡率和DSS消耗量显著减低。结论：2%DSS定量灌胃诱导的小鼠急性结肠炎模型能较稳定地模拟人类UC,均一性高,动物死亡率低。

Comparative Study of Two Acute Colitis Models Induced by Drinking Freely and Quantified Intragastric Administration of Dextran Sulfate Sodium in Mice

Background： The homogenicity of acute colitis models induced by drinking dextran sulfate sodium （DSS） freely in murine is poor and with high mortality rate. Aims： To evaluate the homogenicity of two acute colitis models induced by drinking freely and quantified intragastric administration of 2% DSS in mice, and the resemblance between the colitis model in mice and human ulcerative colitis （UC）. Methods： Acute colitis model was constructed by drinking 2% DSS freely or giving quantified 2% DSS intragastrically in ICR mice. The time and frequency of emergence of symptoms, disease activity index （DAI）, DSS consumption, mortality rate, length of colon, macroscopic assessment of colonic damage （MACD）, histopathologic changes of colon, as well as the peripheral white blood cell （WBC） count and differential count were determined, and the comparison was made between the normal control group and the two model groups. Results： Similar symptoms and histopathologic changes as that in human UC were observed in both model groups. The length of colon decreased and the DAI, MACD, peripheral WBC count and percentage of neutrophils increased as compared with normal controls. The mice in quantified intragastric administration group had higher frequency of occurrence of symptoms and had similar time of emergence of symptoms, lower mortality rate and less DSS consumption than those in free drinking group. Conclusions： Quantified intragastric administration of 2% DSS can induce stably acute colitis similar to human UC in mice with a high homogenicity and low mortality rate.