[Animal modeling] - Comparative study on rat models of ulcerative colitis and damp heat ulcerative colitis

  Objective To establish an animal model suitable for evaluating the efficacy of traditional Chinese medicine prescriptions and new drugs against ulcerative colitis of damp heat syndrome, and to explore the difference and relationship between common ulcerative colitis and UC of damp heat syndrome.

  Methods 24 SD rats were randomly divided into blank control group, UC group and UC+DH group, with 8 rats in each group. Except the blank group, UC group received 5% DSS induction, while UC+DH group rats received "high-fat and high-sugar diet+alternate hunger and satiety+alcohol+high temperature and humidity environment+5% DSS induction" for 29 days. Observe the general condition of rats every day, and carry out disease activity index (DAI) score and colon histopathology score (Geboes). Serum biochemistry tests TG, CHOL, HDL of rats in each group_ C、LDL_ C. The levels of GLU, ALP, LDH, ALT and AST were detected. The concentration of DAO in serum and the activity of MPO, MDA and GSH in colon were detected. The content of cortisol in serum and HSPs, IL-10 and TNF in colon were detected by ELISA- α、 MIP-1 α、 MIP-1 β Expression of.

  Results Both models had intestinal inflammation of different degrees, DAI score and Geboes index increased, and liver function was damaged in different degrees. Differences: Compared with UC group, the above pathological changes were more serious in UC+DH group. In addition, TG, CHOL, LDL in serum of UC+DH group rats_ C. The concentration of ALP, ALT, AST, DAO and cortisol increased significantly, and HDL in serum_ The concentration of C decreased significantly (P<0.05); HSPs, MPO, MDA, TNF in colon- α、 MIP-1 α、 MIP-1 β The level of GSH and IL-10 in colon was significantly decreased (P<0.05).

  Conclusion Both UC models have intestinal mucosa injury and liver injury. The difference is that the damp and hot environment will aggravate the damage of intestinal mucosa of UC rats induced by DSS, and its mechanism may be related to pro-inflammatory, promoting lipid peroxidation, and improving the permeability of intestinal mucosa.