动物造模,应激性胃溃疡动物模型 z-bio 2021-12-09 930

　　(1) Feeding method Adult rats were fasted with water for 24 hours, anesthetized with ether, and fixed the animal's limbs and neck on the rat board in a supine position. After waking up, soak in a constant temperature water tank at 20-23°C, keep the water surface at the height of the xiphoid process of the sternum, and then soak for 20-24 hours. After soaking, the animal was taken out, the skin was wiped dry, bleeding, and an autopsy was performed immediately. First, ligate the pylorus with a thread, then use a syringe to suck 10 ml of 10% formaldehyde solution into the stomach through the esophagus, and then pull out the needle to ligate the door. Cut the esophagus and duodenum at both ends of the two ligatures, and remove the entire stomach. After 30 minutes, it was cut along the large bend, flattened, washed with isotonic saline, and gastric mucosal damage was observed with the naked eye. The degree of damage is expressed by the damage index: point damage is 1 point, less than 1 mm damage is 2 points, 1-2 mm damage is 3 points, 2-4 mm damage is 4 points for major damage, and 5 points for major damage is greater The lesions are 4 mm and 2 mm wide lesions. Multiply by 2, add up all gastric mucosal damage scores for each animal, and use the total score as the gastric mucosal damage index.

　　(2) In the model, after 3 hours of immersion in water, gastric mucosa began to form ulcers, multiple gastric mucosa appeared, hemorrhagic erosions appeared within 7 to 8 hours, and gastric mucosal lesions worsened after 20 hours. The lesion did not pass through the mucosal muscle layer. The most serious is the proventriculus. The lesions are usually distributed along blood vessels and covered with blood clots. Wipe off the blood clot and you will see dark brown filamentous ulcers.

　　(3) Comparative medicine Stress ulcer is a serious stress response that occurs when the body is attacked by a major emergency. When the body is stimulated by an emergency such as severe trauma, severe illness, severe mental stimulation or mental illness, the excitability of the sympathetic nervous system and the parasympathetic nerve-pituitary-adrenal system immediately increases. The former causes gastric vasoconstriction and gastric mucosal blood. Insufficient flow, impaired cell energy metabolism and reduced mucosal barrier function, the latter promotes the increase of gastric acid, pepsin and gastrin secretion, leading to the development of stress ulcers. At present, there are many animal models of acute gastric mucosal lesions established based on the above principles, such as mice, rats, guinea pigs, restraint immersion method, rat hot-water burn method, rabbit crushed femoral fracture method and strenuous exercise. Laws, etc. Because the adrenal system of rats is well-functioning and sensitive to pressure, it is usually used as a model object for replicating animal models of stress gastric ulcer. The rat model replicated by the water immersion suppression method usually shows brown bleeding spots and local mucosal defects in the proventriculus, and the depth does not exceed the muscle layer. Generally, the total length of the ulcer can be used as follows. Take the ulcer index as the ulcer index. The degree of research and judgment. In the process of model replication, attention should be paid to and adjusted the influence of water temperature, animal species, gender, weight and other factors on the degree of mucosal pathological damage. The most important features of this model are simple replication method, high model construction success rate (up to 100%) and excellent experimental repeatability. This is similar to the natural developmental process of human stress gastric ulcer. Anticholinergic drugs and central depressants can reduce its incidence. It is a relatively common experimental model in the field of anti-gastric ulcer drug research, and it is also one of the main models of antipsychotic drug screening experiments in modern medical research.