疾病动物模型,心肌缺血,心肌梗塞 z-bio 2021-03-09 269

　　Methods to replicate animal models of myocardial ischemia and myocardial infarction include ligation of the coronary arteries and some left circumflex coronary arteries, most of which ligate the anterior descending branch of the left coronary artery. For the main coronary arteries, there are also multiple ligations. This method is to ligate multiple branches of coronary arteries at the same time to form an infarcted area. Experience has shown that the area of myocardial infarction depends on the distribution of the myocardium in the ligated coronary artery and the presence of other coronary arteries. The ligation method was established quickly and is still very common today. In addition, oil, Lycoris spores or mercury can be used for diffuse coronary microembolism or selective coronary artery infarction. The former is mainly used in the early stage. In recent years, plastic microsurgery has been invented and manufactured. The number of infarcted areas and the size of the spheres are used to determine the different areas of infarct. The latter targets specific coronary arteries and injects particles or small spherical foreign bodies through catheterization. This method requires skill and strict conditions. Due to charging, there are methods such as coronary thromboembolism. However, due to various conditions, these methods are rarely used. In recent years, the cellulose ring (Ameriod) that swells when exposed to water has been widely used to model the progressive myocardial infarction. The cellulose ring covers the coronary arteries that are expected to be blocked. , It is fixed with a metal ring (stainless steel, etc.) on the outside of the ring, and it may gradually block the coronary arteries more than 2 weeks after the operation. The model is easy to manufacture and has a high animal survival rate. However, even with this method, the pathological basis of human atherosclerosis is still lacking. According to recent reports, domestic pigs fed a high-fat diet can form coronary atherosclerosis and cause myocardial ischemia, which can be solved by feeding atherosclerotic plaque or changing the treatment method. This seems to be a challenging goal. The animals chosen to replicate myocardial infarction models are mainly mammals, and dogs are the most commonly used. Others include rabbits, calves, pigs, guinea pigs and rats. The dog has a reasonable body shape, an obedient temperament, and is easy to train. However, compared with humans, the structure of the coronary blood vessels in dogs is completely different. In particular, the coronary arteries of dogs have a lot of variation, and the collateral anastomosis is abundant, especially the ventricular septal artery, which often troubles researchers. In recent years, it has been reported that the structure of the coronary circulatory system of pigs is similar to that of humans, and an experimental study using domestic pigs or piglets for myocardial infarction has been proposed, but it has not been reported in China. Other arterioles, rabbits, mice, etc. are too small to obtain materials and are rarely used unless under certain conditions. Primates, baboons and monkeys certainly have unparalleled advantages over other animals, but they have very few materials and are usually unusable. The replication method of myocardial ischemia and myocardial infarction model in China:

　　1. Electrical stimulation is a relatively new method established in recent years to cause experimental myocardial ischemia in animals. Adult male rabbits are common in experiments. After anesthesia, two stainless steel needles coated with insulating paint are inserted into the directional device to alternately stimulate the dorsal side of the right thalamus with weak and strong stimulation (weak stimulation is 0.8 to 1.6 mA). , Strong stimulation is 4-8mA) dorsal nucleus is stimulated every 1 to 3 minutes, every 5 minutes.

　　2. Drug methods are also methods that have been adopted in recent years. The most commonly used stereotyped drug is 4% isoproterenol, which is injected subcutaneously into rats at 50 mg/kg body weight. Alternatively, add the drug to 500 ml of saline and inject it from the rabbit ear vein at a constant rate (4 hours). It can be formed by administering 10, 20, 30 mg separately or directly injecting the drug into the abdominal cavity. Ergonovine 0.2 mg/kg body weight can also be injected intravenously into anesthetized dogs, causing coronary artery spasm.

　　3. Coronary artery occlusion is the most common method to create a myocardial infarction model. Usually, a healthy adult dog or rabbit is selected to open the chest cavity and ligate the anterior descending coronary artery after anesthesia to block the blood supply to the myocardium and cause disease. Some people use selective coronary artery cannulation while closing the breast and heart. Insert the catheter through the coronary incision of the anesthetized dog, insert it straight into the bottom of the left sinus along the aortic wall, and inject about 2 cm into the tip. The left coronary artery and 120 mg/kg mercury were injected into the catheter to form an acute myocardial infarction. Some people use a method of tracking around the coronary arteries to incompletely block the coronary arteries, creating a rabbit model of acute ischemia and endangered myocardium. In order to deal with the changes of myocardial ischemia in the natural state, some units have recently used awake dogs as a model of acute ischemia and infarction. First, the dog is anesthetized, and then the 10 mm long coronary artery is separated, connected to the coronary compression ring, and injected with water to block the blood flow in the coronary artery, and wake up the awake dog for myocardial ischemia to observe its response and drug effects. In addition, humans use isolated rat coronary artery ligation to replicate the hyperfine structure of myocardial hypoxic injury model.