【Animal Modeling】-How to establish a rat vaginitis model?

  Objective: To establish a rat model of vaginitis and provide a new model for the development and evaluation of drugs for vaginitis.

  Method: Clinical vaginal samples of Gardnerella vaginalis, Streptococcus albicans and Group B streptococci patients. Twenty-six female rats were pretreated with estradiol benzoate (20 mg/kg) and streptomycin (10 μg each) in the morning, and then injected with vaginal mixture in the afternoon. The other 10 female rats were injected with benzoic acid subcutaneously every day. Take estradiol (20 mg/kg) once for 3 consecutive days. Before grouping, collect vaginal secretions and vaginal dough to observe mixed vaginal bacterial infection. The 20 successfully infected rats were divided into a model group and a drug verification group according to their body weight and the amount of bacteria. Random grouping. 1 day, 5 consecutive days), 10 animals in each group. The normal group and the model group received the same amount of 0.9? sodium injection via vaginal injection. After the last administration, vaginal lavage was collected to detect strain load, and vaginal secretions were collected for vaginal smears, cleanliness, and pH checks. Collect vaginal tissue and observe histopathological changes by HE staining.

  Result: The vaginal wall of rats in the model group was thickened, the stratified squamous epithelial cells were degeneration, necrosis, swelling, the lamina propria were infiltrated, and the edema was obvious, with neutrophils and lymphocytes as the main cells. Single spheres, inflammatory cells, scattered spot hemorrhages, fibroblasts in the papillary area proliferate significantly, and reticular fibers slightly proliferate. The mixed bacteria count, pH value and cleanliness score of vaginal lavage fluid in the model group were significantly higher than those in the normal group (Pu003c0.01), and the negative conversion rate was significantly reduced (Pu003c0.01)). The mixed metronidazole vaginal suppository group can significantly reduce the vaginal mixed bacteria count, pH value, and the cleanliness score of the lavage fluid, which can increase the vaginal conversion rate and reduce the degree of vaginal tissue damage.

  Conclusion: After pretreatment, rats are injected with estrogen and streptomycin sulfate. Mixed bacterial inoculation can successfully establish a mixed vaginal inflammation model in rats, which provides an effective animal model for drug screening and evaluation of the female reproductive system.