动物造模,阑尾炎动物模型 z-bio 2021-12-27 917

　　(1) Regeneration method In adult rats fixed after anesthesia, the abdomen is opened under aseptic conditions, and the intestinal segment (hereinafter referred to as the adjacent intestinal segment) is connected to the appendix, terminal ileum and mesentery. I took out the appendix from the abdomen, I took it out. Place in cavities and walls. Cut the mesangium at the top of the appendix, push the intestinal contents at the top of the appendix into the intestinal cavity at the proximal end of the appendix, and ligate 1 cm from the top of the appendix. Place the tip of the ligated appendix between the root of the ileum and the adjacent small intestine. The root of the ileum and the adjacent intestine are sutured with a small round needle and a thin silk thread (000) (penetrating only the serous muscle layer), and the ligated appendix is buried under it. Then along the end of the ileum from the distal end to the proximal end, close the corresponding position of the adjacent intestine with 1-2 stitches, and implant all the appendix under the sutured intestine. All the external intestinal segments are sent into the abdominal cavity, the abdomen is closed with two sutures, the wound is wrapped with sterile gauze, and then returned to the cage for observation. Or, after anesthesia, skin preparation, disinfection and draping, an adult rabbit is fixed on the operating table, a 6 cm central abdominal incision is made aseptically, the appendix is lifted from the cecum, and the fourth is applied to the appendix wall Root silk thread. It is located at the bottom of the appendix. Connect the appendix to the mesangium, then put the appendix back into the abdominal cavity, and close the abdomen layer by layer. After the operation, the temperature of the animal was measured at the designated time point, the content of the necrotizing appendicitis cavity was cultured, the size of the cyst or necrotic appendix was detected, the gross pathological observation was performed, and the tissue morphological changes were checked under a microscope.

　　(2) 15 days after the operation, the model is characterized by purulent necrosis of the appendix, fibrous cysts on the outside, and high bacterial content. The success rate of this model is almost 100%. 6-12 hours after the operation, the appendix is congested, edema and thickened. Within 12 to 24 hours, the appendix swells and thickens significantly, and external pus is attached to the surrounding intestine. I saw part of the appendix wall. Hemorrhage was found, located in the appendix. Exudation of exudate occurred. The surrounding intestine attached to the appendix abscess also showed obvious edema, congestion and the formation of mesenteric abscess. Bacterial culture of ascites can lead to the growth of E. coli. After 24 hours, the rabbit's body temperature can rise to about 40°C. Throughout the modeling process, the model animals were sluggish, did not eat or drink, had full abdomen, and died within 2-4 days. (3) Comparative medicine The two main causes of appendicitis are bacterial infection and obstruction of the appendix cavity. In this experiment, the appendix tube was artificially ligated, which blocked the appendix cavity and induced an acute appendicitis model. The etiology of this model is similar to that of the clinic, and its etiology and pathological types are also similar to those of humans. After 6-12 hours, the rabbit appendix showed congestion, edema and hyperplasia, pathological examination confirmed acute simple appendicitis. Twelve to twenty-four hours after the operation, the appendix was visibly swollen, the serous membrane was highly hyperemic, and purulent exudate appeared. In the abdominal cavity containing a large amount of Escherichia coli, the pathological changes are acute appendicitis; more than 24 hours after the operation, appendix necrosis, necrotic perforation and pathological changes are very acute neurogenic appendicitis. Rats or rabbits are often used to replicate appendicitis models. Among them, the replication method of the rat model is simple, the operation cycle is short, and the whole process only takes 10-15 minutes, including animal body temperature, bacterial culture of necrotic appendix lysate, cyst or necrotic appendix. It is objective and clear. Due to its high success rate due to changes in size and pathological morphology, it can be used to study acute abdominal appendix abscess, and can be used as a model for drug activity screening and efficacy evaluation. Used to prevent and treat appendix abscess or infectious inflammation. However, when creating the model, the intestinal segment used to implant the necrotic appendix should be completely packaged to prevent the contents of the necrotic appendix from flowing into the abdominal cavity and causing diffuse peritonitis.

　　(3) Since the length of the ligated appendix is positively correlated with the condition, it is necessary to control the length of the appendix ligation at an appropriate level. Usually the length can be controlled within 3 cm. After all, it is not easy to form a perfect package. ligation. Too many suture needles do not meet the physiological characteristics and are more likely to form intestinal obstruction. ③In order to prevent artificial intra-abdominal contamination, all operations must follow the principle of sterility and place the sutured intestinal part in a better position in the abdominal cavity to avoid intestinal infarction and animal death. returned. Although the survival time of the rabbit model is very short, its etiology and pathological symptoms are close to the clinic, and it is particularly suitable for studying the development and treatment options of acute appendicitis. When copying the model, care must be taken not to damage the appendix’s arteries and veins during the operation to ensure the appendix’s blood supply.