【摘要】 为探究产芽孢菌对胃肠运动的调节作用及其潜在机制，利用氯仿提取法在体外提取健康志愿者粪便中的产芽孢菌菌液，并通过聚合酶链式反应验证产芽孢菌菌液的提取效果。运用抗生素鸡尾酒法建立伪无菌（pseudogermfree,PGF）小鼠模型，并用粪便菌悬液涂板实验及肠杆菌基因间保守重复序列-聚合酶链式反应（enterobacterial repetitive intergenic consensus sequences-polymerase chain reaction,ERIC-PCR）进行模型评价。PGF小鼠造模第11天，小鼠粪便悬液涂板无明显菌落且ERIC-PCR条带显著减少，表明实验造模成功。成模后，将小鼠随机分为模型组和产芽孢菌定殖组，进行两周的产芽孢菌定殖，采用荧光定量核酸扩增检测方法检测产芽孢菌定殖情况。通过小肠推进率和胃残留率实验测定胃肠动力，并收集小鼠结肠和血浆，检测其中五羟色胺（5-hydroxytryptamine,5-HT）的含量以及结肠中色氨酸羟化酶1(tryptophan hydroxylase 1,TPH1)的表达水平。实验结果表明，产芽孢菌定殖后，小鼠胃残留率显著下降（P<0.05），小肠推进率显著升高（P<0.01）,粪便中瘤胃球菌属、扭链瘤胃球菌属、多尔氏菌属含量显著上升，结肠和血浆中5-HT含量明显提高，但是结肠中TPH1表达明显下调。表明产芽孢菌可通过提高肠道和血浆中5-HT的含量水平以促进胃肠运动。更多还原

【Abstract】 The regulation of gastrointestinal motility by spore-forming microbes and the potential mechanism were investigated. Spore-forming microbes were extracted in vitro from the feces of healthy volunteers using the chloroform. The extraction efficiency was confirmed by polymerase chain reaction(PCR). The pseudo germ-free mouse model created using the antibiotic cocktail approach was evaluated by a fecal bacteria suspension coating experiment and Enterobacterial Repetitive Intergenic Consensus Sequences-PCR(ERIC-PCR). The fecal suspension coating plate collected and processed on day 11 of PGF mice modeling did not produce visible colonies.The ERIC-PCR bands were greatly diminished,demonstrating the successful establishment of the model. The mice were randomly divided into model and spore-forming microbe groups. Transplantation in the spore-forming microbes group was performed by gavage. The colonization of spore-forming microbes was confirmed by quantitative PCR. Intestinal thrust and residual gastric rates were used to assess intestinal motility. The contents of 5-hydroxytryptamine(5-HT,serotonin)and tryptophan hydroxylase 1(TPH1)in the colon and plasma were determined. Following colonization,the residual gastric rate of mice was significantly decreased(P<0.05),while the intestinal thrust rate was significantly increased(P <0.01). The contents of Ruminococcus,Ruminococ-cus＿torques＿group,and Dorea in feces were significantly increased. The levels of 5-HT in the colon and plasma were significantly increased,but the expression of TPH1 in the colon was significantly downregulated. The results indicate that spore-forming microbes promote gastrointestinal motility by increasing intestinal and plasma serotonin levels.更多还原