SD rats were randomly distributed into groupⅠ(immune-combmethod),groupⅡ(TNBS/ethanol),groupⅢ(50% ethanol) and groupⅣ(control).The rats in groupⅠwere sensitized 2 times by antigen made of rabbitcolonmucosa in 2-week intervals.After abrosia for 24 hours,each rat in four groups received enema of 0.65 ml different fluids,which wereTNBS 100mg/kg +50%ethanol for groupⅠand Ⅱ,50%ethanol for group Ⅲ,and normal sodium for control group.Rats were sacrificed on day 1,21 and week 8,12 after enema to observe the macroscopical focus of infection in bowels and the microscopical changes.
Results:
The typical erosion and ulcer changes appeared in groupⅠandⅡ,and there was accompanying pathological changes in the end piece of ileum in groupⅠ.The pathological changes for groupⅠcould keep for 8 weeks,while those for group Ⅱtrended to heal 3 weeks later.The pathological changes in groupⅢonly were hyperemia,oedema and a few anabrosis or superficial ulcer,keeped for 21days.There was no tissue damage in group Ⅳ.
Conclusion:
Immune-combmethod is comparatively the ideal method to establish the model,,because it has a good reproducibility,a long persistence time,and the pathological changes resemble more to those of man..