Histopathological features of the rat ileum after Shigella flexneri infection

Luo Su-yi; Wang Xi-yun; Li Jin-tao

doi:10.3969/j.issn.2095-4344.2016.49.017

Abstract：BACKGROUND:Bacil ary dysentery is one of the most common enteric infectious diseases in summer and autumn that is mainly caused by Shigel a. <br> OBJECTIVE:To analyze the pathological features of the rat ileum after Shigel a flexneri infection. <br> METHODS:Total y 30 male Sprague-Dawley rats were enrol ed and equal y randomized into three groups. Rats in non-streptomycin and streptomycin groups were firstly treated with normal saline and 50 g/L streptomycin sulphate via gastric lavage, and then given gastric lavage of 9×108 CFU/mL Shigel a flexneri. Rats were given no any treatment as control group. 14 days later, morphological changes of the rat ileum were observed through hematoxylin-eosin staining. <br> RESULTS AND CONCLUSION:(1) After Shigella flexneri infection, the rat distal ileum and rectum were characterized by mucosal edema and hemorrhage, neutrophilic granulocyte exudation, pseudomembrane formation and destruction of goblet cells with hemorrhage. There were obvious fibrin exudation on the necrotic mucosal surface that constituted the pseudomembrane with necrotic debris, leukocytes and erythrocytes. After mucosa defulvium, non-uniform and superficial ulcers were mainly visible at the mucosa. (2) The occurrence time of positive systems, temperature and body mass before and after Shigella flexneri infection showed no significant differences among rats (P>0.05). (3) These results suggest that the rat distal ileum and rectum after Shigella flexneri infection present the characteristic morphological futures of bacillary dysentery;therefore, it can be used as the animal model to undergo in-depth research about the etiology, pathogenesis and treatment of bacillary dysentery.