Establishment Shigella Flexneri Infection Model In Rats And Research In The Effect Of Bifidobacterium Treatment And Mechanism

Objective1. Establishment Shigella flexneri infection model in SD rats to provide thefoundation for further research of bacillary dysentery pathogenicmechanism and prevention.2. Explore the effect of Bifidobacterium treatment in Shigella flexneriinfection rats model.Method：1. First, induced dysbacteriosis in the normal rat by streptomycin sulphate. Theninfected Shigella flexneri through stomach irrigation to establish infection ratsmodel according to the clinical feature and pathological diagnosis.2. Detected the Shigella flexneri counts in faeces after treatment byBifidobacterium in infection rats model.3. Detected the blood IL-2and intestinal mucous sIgA content with ELISAafter treatment by Bifidobacterium.4. Detected the rat splenic cell proliferation by MTT to evaluate the role ofimmunity enhancement of Bifidobacterium in SD rats model by spleenindex and the thymus index.Result： 1. The infection rats appeared thin faece in clinical feature，the intestinal mucosanecrosis fall off in pathological slides to means the infection modelestablished successfully.2. There are significant differences of Shigella flexneri counts in faece betweeninfection group with the group these of blank control and NS control.3. The level of blood IL-2and intestinal mucous sIgA have significantdifference of between infection group with the group these of blank controland NS control.4. The spleen index induced by dysentery antigen and the thymus indexsignificantly higher than not treatment group.Conclusion：1. The Shigella flexneri infection model in SD rats established successfully.2. The Shigella flexneri content in faece of infection model rats could reducerapidly after Bifidobacterium treatment.3. Bbifidobacterium treatment could promote the rats to secrete the IL-2andsIgA.4. Bifidobacterium treatment could promote the spleen cells proliferation.