三种小鼠术后肠麻痹模型的比较研究

Comparative study on three preparation methods of mouse postoperative ileus models

目的观察3种不同方法制备的小鼠术后肠麻痹模型胃肠道运动的变化,比较各模型特点及其是否适合于药物评价。方法分别采用空气暴露法、摩擦法和挤压法制备术后肠麻痹小鼠模型。测定小鼠胃排空率,小肠推进率,小肠各段葡聚糖蓝-2000相对百分率,并对小鼠十二指肠、空肠、回肠和结肠进行HE染色,观察小鼠肠壁各层组织病理变化。结果与正常对照组比较,仅挤压组小鼠胃排空率受到显著抑制,且具有统计学差异(P<0.01);空气暴露组、摩擦组和挤压组小鼠小肠推进率均受到抑制,但仅摩擦组和挤压组有统计学差异(P<0.01)。病理学检测结果表明,与正常对照组比较,空气暴露组、摩擦组和挤压组小鼠在十二指肠无明显差异,而在空肠部位,挤压组小鼠肠道黏膜及黏膜下层有大量出血及炎性细胞浸润。在回肠和结肠部位,摩擦组和挤压组均出现不同程度的炎性细胞浸润,挤压组小鼠在回肠部位有出血。结论 3种复制术后肠麻痹模型的方法均能抑制小鼠肠道运动。空气暴露法模型损伤最轻;挤压法模型肠道损伤较重,可用于术后肠麻痹发病机制的研究;而摩擦法模型损伤力度适中,较适合作为药物筛选和评价模型。

Objective By observing the motility changes of the gastrointestinal tract in mouse postoperative ileus（POI）models prepared with three different methods,this study aims to compare the features of three types of models,and judge their suitability for drug evaluation. Methods Three methods were conducted to prepare the mouse POI models：air exposure,friction and extrusion.In the experiment,the gastric emptying rate,intestinal propulsive rate as well as the relatively percent dextran of blue-2000 in intestinal paragraphs were taken down to evaluate the motility of gastrointestinal tract. Meanwhile,the duodenum,jejunum,ileum and colon of mice were stained in HE method to observe the histopathological changes of each layer in mouse intestinal wall. Results When compared with the control group,the gastric emptying rate of the squeeze-only group was significantly suppressed（P〈0.01）. The intestinal propulsive rate in the air exposure group,the friction group and the extrusion group were all suppressed,only the friction group and the extrusion group had statistical difference（P〈0.01）. The relative percent of dextran blue-2000 in intestinal paragraphs in mice also show that the motility of the mouse gastrointestinal tract in both the friction and extrusion groups was significantly inhibited.Judging from the results of HE staining,the duodenums of mice in the air exposure group,friction group and extrusion group did not show much difference when compared with the control group. While for the jejunum,the intestinal mucosa and submucosa of mice in the squeeze group had a large quantity of hemorrhage and inflammatory cell infiltration. For the ileum and colon,the friction and extrusion groups showed different degrees of inflammatory cell infiltration,and the mice in the extrusion group suffered from ileal hemorrhage. Conclusion All the three preparation methods of mouse POI models can inhibit the intestinal movement of mice. The effect of the air exposure method causes the light injury. The extrusion method,which causes more serious injury,could be used in the study of the pathogenesis of postoperative ileus.The friction method that has a moderate damage to the intestine,is more suitable for drug screening and evaluation.