抗生素所致菌群失调腹泻小鼠肠道乳糖酶活性的研究

摘要

The aim of this study was to investigate the effect of antibiotics on the lactase activity in intestine of dysbacteriotic diarrhea mice caused by antibiotic mixture.The mice were randomly divided into two groups.The model group was treated with antibiotic mixture composed of cefradine and gantamicin sulphate,the normal group was treated with sterile water.The lactase ctivity in the intestinal contents and the intestinal mucosa in mice was determined with ONPG method.The results showed that the lactase activity level of intestinal contents in the model group was significantly lower than that in the normal group since the second day,and the diffience between the two groups was significant since the forth day (p＜0.05).The differences of the lactase activity level of the front segment,the middle segment and the posterior segment of the mice intestinal mucosa were very notable between the model group and the normal group since the fifth day (p＜0.01).Our findings indicated that antibiotics obviously affected the activity of intestinal lactase in mice,and the mechanism of diarrhea caused by antibiotics may be related with the decrease of the lactase activity level in intestine.%为探讨抗生素造模对菌群失调小鼠肠道乳糖酶活性的影响,本研究采用硫酸庆大霉素和头孢拉定混合抗生素制备菌群失调腹泻小鼠模型,造模成功后分别提取模型组和正常组小鼠第1d至第7d肠道内容物及肠粘膜.将肠粘膜平均分成前、中、后3段,每段约10 cm,用ONPG法分别测定肠内容物及各段肠黏膜所含乳糖酶活性,结果表明,造模第2d,模型组肠内容物中乳糖酶活性均明显低于正常组,第4d开始两组差异显著(p＜0.05).模型组肠前段黏膜乳糖酶活性自第3d开始与正常组对比差异极显著(p＜0.01)、肠中段、肠后段黏膜乳糖酶活性分别自第2d、第3d开始与正常组对比差异显著(p＜0.05),且各肠段粘膜自第5d开始与正常组对比差异极显著(p＜0.01).上述结果表明,抗生素造模显著影响小鼠肠道乳糖酶活性,且抗生素所致菌群失调性腹泻与肠道乳糖酶活性降低有关.