Abstract: Objecive To observe the effects of XiaoChaihu KeLi combined with Levofloxacin on Escherichia coli ( E. coli) result on antibacterial and antidiarrhea in vivo. Method The seventy Kunming mice (weighing (20±2) g, sex in half) were divided into seven groups, and different concentrations of E. coli bacterial were intraperitoneal injection, which to determine the concentration of bacterial suspension of minimum lethal dose ( MLD) . The fifty Kunming mice were divided into five groups, which were model group, normal saline group, levofloxacin group, Xiaochaihu granule group and combined treatment group ( levofloxacin and Xiaochaihu granule ) . The bacterial suspension concentration of minimum lethal dose ( MLD) in mice was determined. In the in vivo antibacterial test, the bacterial diarrhea model of mice was established by intraperitoneal injection of E. coli suspension ( MLD concentration) . After 15 days of intragastric administration of corresponding drugs, the protective effect of combined drugs on lethal E. coli infection in mice was explored. The effects of combined administration on diarrhea index and organs of mice infected with E. coli and on intestinal propulsion rate of mice were explored after 7 days of gavage of corresponding drugs. Result The combined drug had a good protective effect on diarrhea induced by E. coli infection in mice, and the survival rate was 90%, which was statistically significant compared with the levofloxacin group and the Xiaochaihu granule group ( P<0. 05) . Combined drug group significantly improved the diarrhea symptoms of mice, compared with model group and Xiaochaihu granules group, diarrhea index of combined drug group had significant statistical significance ( P<0. 01) . Compared with the levofloxacin group, the diarrhea index of the combined treatment group was statistically significant ( P <0. 05) . The combined drug group protected the organs of mice and reduced the effect of diarrhea caused by E. coli infection on the toxicity of the organs, it could also improve the immune organ coefficient and improve the body immunity. Compared with model group, blank group, levofloxacin group and Xiaochaihu granule group, the thymus organ coefficient and spleen organ coefficient of combined medication were statistically significant ( P<0. 05) . Compared with levofloxacin group and model group, the liver organ coefficient and kidney organ coefficient in the combined treatment group were statistically significant ( P < 0. 05 ) , compared with blank group, were nonstatistically significant ( P > 0. 05 ) . Combined drug improved intestinal motor function of diarrhea mice caused by E. coli infection. Compared with model group and blank group, small intestinal propulsion rate had significant statistical significance ( P < 0. 01) , Compared with levofloxacin group and Xiaochaihu granule group, there were statistical significance ( P < 0. 05) . Conclusion The combination of Chinese and Western medicine have a synergistic effect, improve the antibacterial and anti-inflammatory effect, reduce the use of antibiotics, at the same time, it can play the immunity-enhancing effect of Xiaochaihu KeLi, improve the body’ s resistance to foreign evil, improve the survival rate. The result of this study provide experimental basis for the clinical combination of bacterial diarrhea.
