动物造模,药效评价,肠粘连 z-bio 2024-08-26 416

　　(1) Method of replication: Adult rats were fasted and kept in water for 12-16 hours. After intraperitoneal injection of pentobarbital sodium at a dose of 40mg/kg body weight, the rats were anesthetized and fixed supine on a surgical plate. The abdomen was routinely depilated and the skin was disinfected. A sterile gauze was placed in the middle of the lower abdomen, and a 2-3cm incision was made to remove the cecum. The cecum was placed on dry gauze for 5 minutes to dry the cecal serosa. Then, the entire cecal serosa was gently scraped with an dissecting blade for about 10 times, causing slight spotting of blood on the cecal wall. An appropriate amount (1-2 drops) of anhydrous ethanol was dripped onto the wound. After the cecum is returned to its original position in the abdominal cavity, hemostatic forceps are used to clamp the corresponding abdominal walls on both sides of the incision with the skin as the center. A No. 4 silk thread is used to symmetrically ligate the abdominal walls on both sides (with a span of 0.5cm), causing local ischemia. The incision is sutured in two layers with 1-0 silk thread. Animals were housed separately after surgery and euthanized on the 7th day. Score the degree of adhesion according to the following criteria: ① No adhesion at all: 0 points. ② There is only one adhesive joint between the internal organs or between the internal organs and the abdominal wall: 1 point There are 2 adhesive bonds between the internal organs or between the internal organs and the abdominal wall: 2 points More than 2 adhesive bonds: 3 points. ⑤ Direct adhesion of internal organs to the abdominal wall: 4 points.

　　(2) The adhesion rate of the animal model established using this method is about 90%. Multiple adhesions can be formed around the cecum and incision, and adhesions can be formed between the cecum and small intestine, small intestine and incision, and small intestine. When evaluating the degree of adhesion, there is no need to peel off the serosa, which is not easy to bleed. The preparation method of this model is simple, economical, and has a high success rate. It shares similarities with the mechanism and pathological changes of human intestinal adhesions in clinical practice; Moreover, the mortality rate of model animals is low, and the level of adhesion data is easy to classify and evaluate.

　　(3) Comparative medicine shows that intestinal adhesions are one of the most common diseases in clinical practice, and they are also the main cause of postoperative complications such as intestinal obstruction, infertility, and pain. Postoperative intestinal adhesions are still an unsolved surgical problem in clinical practice. A research report suggests that 80% to 90% of patients who have undergone abdominal surgery may experience postoperative intestinal adhesions. The formation mechanism of intestinal adhesions in patients is relatively complex. One possible factor is that during abdominal surgery, the abdominal cavity may be damaged and stimulated by mechanical, chemical, and temperature factors, which can cause non-specific inflammation of the peritoneum and serosa, leading to inflammatory exudation at the site of injury. Due to the limitations of the fibrinolytic system and phagocytic ability, coupled with the inactivation of fibrinolytic enzymes by oxygen free radicals and lysozyme in the body, the fibrinolytic ability is weakened and cellulose precipitation occurs, ultimately forming adhesions. At the same time, ischemia is another important factor in the formation of intestinal adhesions. Due to the tight suturing of the peritoneum or serosa during surgery, local ischemia can easily cause vascular adhesions in the peritoneum or serosa in contact with it. Except for rodent intestinal adhesion models, both rabbits and dogs can replicate intestinal adhesion animal models, which are easier to observe and evaluate than mice. If an adult New Zealand rabbit weighing about 2.5kg is anesthetized by intraperitoneal injection of sodium pentobarbital at a dose of 40mg/kg, a midline incision is made into the abdomen, and the ileal serosa is manually rubbed with a dental coarse grinding wheel on the ileal wall 2cm away from the ileocecal area until local bleeding occurs, causing a rough surface of the ileal serosa. Then, the incision is sutured in two layers with 1-0 silk thread to establish an animal model of ileal adhesions. At present, surgical methods are still the most commonly used approach in the preparation of intestinal adhesion models. The use of surgical trauma to stimulate the abdominal cavity of rats can cause postoperative intestinal adhesion. Among them, the preparation of cecal animal models is more ideal. The method is simple, easy to operate, the experimental conditions are stable, the controllability is good, the animal mortality rate is low, and the observation indicators can be graded and evaluated and statistically analyzed. However, the practical value of the ileal animal model is not as good as that of the cecal animal model due to factors such as the degree and time of stimulation, and the difficulty in quantifying the degree of intestinal adhesions.