嗜酸乳杆菌合生元对抗生素相关腹泻大鼠肠道菌群和肠黏膜损伤的作用

背景：抗生素相关腹泻（AAD）是抗生素治疗最常见的不良反应。随着抗生素应用的日益广泛,AAD病例逐年增多。目的：探讨嗜酸乳杆菌与低聚异麦芽糖（IMO）组成的合生元对AAD大鼠肠道菌群和肠黏膜损伤的作用。方法：50只大鼠随机分为5组。四组模型组以盐酸林可霉素灌胃6d诱导AAD,之后其中一组予0.9%NaCl溶液灌胃7d作为自然恢复组,另三组分别予低、中、高剂量合生元灌胃7d。正常对照组仅予0.9%NaCl溶液灌胃7d。行肠道菌群分析后处死各组大鼠,行肠黏膜形态学观察和图像分析。结果：AAD模型大鼠肠道菌群失调,小肠黏膜水肿、糜烂、萎缩、坏死、脱落,绒毛排列紊乱、稀疏。不同剂量合生元组肠道菌群失调均有所改善,与正常对照组相比无明显差异;小肠黏膜病变均轻于自然恢复组,尤其是中、高剂量合生元组,小肠黏膜厚度、绒毛高度和隐窝深度较自然恢复组显著增加（P〈0.01）。结论：嗜酸乳杆菌合生元对AAD大鼠肠道菌群失调和肠黏膜损伤有一定治疗作用。

Effect of Lactobacillus acidophilus Synbiotics on Intestinal Flora and Mucosal Injury in Antibiotic-associated Diarrheal Rats

Background： Antibiotic-associated diarrhea （AAD） is a common complication of antibiotic use. The incidence of AAD is increasing in recent years because of the wide application of antibiotics. Aims： To investigate the effect of synbiotics composed of Lactobacillus acidophilus and isomaltooligosaccharide （IMO） on intestinal flora and mucosal injury in AAD rats. Methods： Fifty rats were randomly allocated into 5 groups. Forty model rats were given 6-day lincomycin hydrochloride intragastrically to induce AAD at first, and then received 0.9% NaCl solution （10 rats, spontaneous recovery group） or synbiotics at low, moderate, and high dosages （10 rats in each group） for 7 days. Ten rats administered with 0.9% NaCl solution for 7 days were served as normal controls. All the rats were sacrificed after determination of intestinal flora. The morphological changes of intestinal mucosa were assessed with light microscopy and image analysis. Results： The AAD model rats showed intestinal flora disorder and a series of pathologic changes in small intestinal mucosa, including edema, erosions, atrophy, necrosis and epithelial ablation with villous derangement. The intestinal flora of the rats administered with synbiotics improved and reached a similar level as that of normal controls. Compared with spontaneous recovery group, synbiotics could alleviate the above-mentioned mucosal injuries, especially in moderate and high dosage groups, the thickness of small intestinal mucosa, the height of villi and the depth of crypts were increased significantly （P〈0.01）. Conclusions： Lactobacillus acidophilus synbiotics has therapeutic effect on intestinal flora disorder and mucosal injury in AAD rats.