动物造模,溃疡性结肠炎,药效评价 z-bio 2024-05-28 1146

　　1. Animal modeling materials: Adult rats, male and female, weighing 250-400g; Medications: physiological saline, formaldehyde.

　　2. Method of modeling: Take the colon contents of a healthy rat, draw a line on an eosin blue plate, culture at 37 ℃ for 24 hours, amplify typical colonies, and perform numerical identification. Once confirmed as Escherichia coli, store in the refrigerator for future use. Before immunization, take the bacterial strain and amplify it, then use formaldehyde to kill the bacteria, wash twice with physiological saline, and adjust the concentration to 1.2 × On the 1st day, 0.2ml of bacterial suspension was injected into the plantar area of rats to the 8th power of 10. On the 10th and 17th days, 0.4ml and 0.6ml were injected subcutaneously at multiple points on the abdomen and back, respectively. On the 24th day, 1.2ml was injected intraperitoneally.

　　3. The principle of modeling is to use the normal bacterial population of rats as antigens, and as the number of immunizations increases, it causes immune responses in rats.

　　4. Changes after modeling: As the number of immunizations increases, ulcers and diffuse inflammation gradually appear in the colon wall of rats, accompanied by a decrease in cellular immunity and an increase in circulating immune complexes. After 2 weeks of immunization, there were soft stools and positive occult blood in stools. After 3 weeks, there were mucous stools accompanied by decreased appetite, weight loss, fatigue, and loose hair. After 31 days, typical ulcerative colitis symptoms were observed and gradually worsened. Histopathological examination met the conditions for ulcerative colitis.

　　5. Notes: The technical key of this model is the need for certain facilities and techniques for the preparation of Escherichia coli suspension. This method has simple experimental operation, convenient antigen source, high success rate, and similar symptoms to clinical practice, but the experimental cycle is long.