[Animal modeling] - Establishment of levofloxacin resistant mouse model

  Objective: To detect the effect of low concentration of levofloxacin on the pneumonia model of mice infected with Pseudomonas aeruginosa (PA), and explore the method of levofloxacin resistance

  Methods: The pneumonia model of mice infected with PA was used. The mice in each experiment were randomly divided into groups according to their weight. Different concentrations of bacterial fluid, infection times, and drug administration methods were used to analyze the therapeutic effect of levofloxacin with the changes of body weight and lung index of mice as evaluation indicators. Results The feasibility of establishing the model was discussed × 109 cfu/mL), the lung index of model group 1 and model group 2 was significantly different from that of normal group (P<0.01); There was no significant difference between levofloxacin group 2 and model group 2. Low concentration levofloxacin had no significant effect on PA (1 × 1010cfu/mL) single time infected mice, model group 1 and model group 2 had significant differences compared with the normal group (P<0.01). Levofloxacin group 3 had no significant difference compared with model group 2. Levofloxacin group 1 and 2 could significantly reduce the lung index of model group; In the experiment of PA repeatedly infecting mice, there was a significant difference between model group 1 and model group 2 and the normal group (P<0.01). There was no significant difference between levofloxacin group 2 and model group 2. In each experiment, the weight of mice decreased compared with the normal group on the second day after infection, and there was no significant difference in the results

  Conclusion: Under the experimental conditions, low concentration of levofloxacin has a significant effect on PA (1 × 1010cfu/mL) single infection of mice and repeated infection of PA mice with low concentration of levofloxacin, the animal model can simulate the phenomenon of drug resistance in clinical to a certain extent