动物造模,药效评价,结肠炎 z-bio 2024-07-25 377

　　1. Modeling material animals: BALB/c mice, 7-8 weeks old, weighing 25-30g; Medications: Oxazolidone, Metoclopramide, Ethanol.

　　2. Modeling method: Intramuscular injection of Su Mian Xin anesthesia was used to model mice. The abdominal skin was shaved (2cm × 2cm), and the model group was treated with 0.2ml of 3% oxazolone (dissolved in 100% ethanol) applied to the skin; Repeat the application once a day later. After 5 days, a 2mm diameter silicone tube was inserted into the mouse intestine from the anus, about 4cm deep. The model group was injected with 0.15ml of 1% oxazolone (dissolved in 505 ethanol).

　　3. Modeling principle: Oxazolidone induces colitis in mice.

　　4. After modeling, there were general changes. Two days after the second application of oxazolone to the model group mice, the skin at the application site showed redness and swelling, and some mice had skin ulceration. The model group mice showed weight loss and diarrhea 24 hours after enema, and the diarrhea reached its peak on the 3rd to 4th day. Some mice had bloody stools on the naked eye, and the diarrhea lasted for about a week before gradually turning into soft stools. After 2 weeks, the stool characteristics returned to normal.

　　After 24 hours of enema, the model group mice showed congestion and edema of the distal colon mucosa, with continuous distribution of lesions. Microscopically, the lesions were characterized by epithelial cell loss, erosion, and shallow ulcer formation, decreased goblet cells, decreased glandular density, and inflammation limited to the mucosa and submucosal layer. Multiple inflammatory cell infiltrates were observed in the submucosal layer, with neutrophil infiltration being the main early stage and lymphocyte, monocyte, and plasma cell infiltration being the main stage one week later, with a few neutrophils and eosinophils visible; Colitis can last for about 2 weeks.

　　The activity of myeloperoxidase (MPO) in the diseased colon tissue of the model group mice was significantly increased within one week after enema (24 hours, 3 days, and 7 days) compared to the control group. The IL-4 content in the diseased colon tissue of the model group mice was significantly increased compared to the control group within one week after enema (24 hours, 3 days, and 7 days), while the TNF - α and interferon - γ (IFN - γ) content were basically normal.