动物造模,药效评价,溃疡性结肠炎 z-bio 2024-08-20 273

　　1. Modeling material animals: Healthy Wistar rats, half male and half female, weighing approximately 200g; Healthy rabbits; Drug: Complete Freund's adjuvant, formaldehyde solution.

　　2. Modeling method: Fresh rabbit colon mucosa was used to prepare tissue homogenate, which was centrifuged at a speed of 4000r/min for 30 minutes. The supernatant was purified, and the protein content was measured using Coomassie Brilliant Blue staining method. An antigen emulsion was prepared with an equal amount of complete Freund's adjuvant. The normal group is fed normally every day without any treatment; On the first day, the model group immunized rats were injected with antigen emulsion, which was injected into the left plantar, inguinal region, and back of the rats at a dose of 8mg (approximately 0.86ml) each. On the 15th day, the same amount of antigen emulsion was injected into the right plantar, inguinal region, and back using the same method. On the 29th day, the model group rats were enema with 2% formaldehyde solution, left for 1 hour, washed with physiological saline, and then enema with 1 ml of antigen solution (without adjuvant), left for 2 hours.

　　3. The principle of modeling is that sensitization of allogeneic colonic mucosal tissue and formaldehyde stimulation can lead to colitis in animals.

　　4. Changes after modeling: Rats in the immunized model group began to experience soft and loose stools, as well as symptoms such as decreased appetite, fatigue, vertical hair, arching back, and mucous bloody stools at week 3, with significant weight loss; The normal group of rats had normal stool and a slight increase in body weight, with no other changes.

　　Normal group rats: The colonic mucosa is intact, without infiltration of inflammatory cells or ulcers, the mucosal epithelium is intact and continuous, the glandular arrangement is neat, the vascular fiber endoplasmic reticulum in the submucosal lamina propria is normal, and there are no abnormalities in the muscle layer; Model group rats: There is a large infiltration of inflammatory cells on the mucosal surface, with large ulcerative areas visible, some of which can penetrate deep into the muscle layer, and severe glandular damage.