Establishment and evaluation of specific antibiotic-induced Inflammatory bowel disease (IBD) model in rats

Abstract

Background: Physical and chemical methods have been established for rat enteritis model, but antibiotic induction has been relatively rare. This article aims to establish and evaluate rat model of Inflammatory bowel disease (IBD) using antibiotics Methods: Eighty four female SD rats were divided into A-G group according to the dosage and method of antibiotics, among which group A was the control group and others were treated groups. The drug was stopped on the 7th day, the modeling period was 1-7 days, and the recovery period was 8-15 days. Half of the animals were dissected on 11th day and the other animals were dissected on 15th day. Record the food and water intake, body weight, and fecal weight for 2 hours on different days. Number of defecation of each rat was counted for analyzing diarrhea. Nine intestinal flora were analyzed by bacterial culture and three strains were analyzed by quantitative PCR. TNF-α, IL1-β, IL-6 and CRP in abdominal aorta blood were detected and analyzed. Colon and rectal tissues were pathologically examined for inflammation and scored. Results: Rat weight, food intake, water intake, and two-hour feces were significantly different (P = .04, .016, <. 001, .009). Compared with group A, there were significant differences in 9 kinds of flora in the experimental group (all P <.001). Significant diarrhea existed in B-G rats dependent on drug (all P<.001). Bacteroides, Faecalibacterium prausnitzii, and Dialister invisus concentrations were analyzed by Quantitative real time polymerase chain reaction (q-PCR) and showed significant differences in groups A, C, and F (p = .033). There were significant differences about TNF-α, IL1-β, IL-6 and CRP between the groups (all P<.001). The colonic and rectal pathological inflammation scores of other groups were significantly different from those of the control group (all P <.001). Conclusion: Specific antibiotic-induced enteritis model in SD rats is feasible.