动物造模 z-bo 2022-10-07 561

　　[Modeling mechanism] Similar to thoracotomy, the difference between electrocautery coronary artery and ligation is that electrocoagulation will cause coronary artery occlusion and local myocardial tissue necrosis due to electric current, resulting in myocardial infarction. Corresponding myocardial damage that directly caused myocardial infarction in model animals. [Modeling method] Taking rats as an example, Wistar rats weighing about 250 g and pentobarbital sodium 10 ml/kg were selected for intraperitoneal injection, and atropine 20-30μg/kg was injected intraperitoneally before intubation. First intubate the trachea and connect the ventilator. Fix the limbs of the rat in the supine position, remove the hair, and disinfect the bed sheets. Make a vertical incision of 1.5 to 2.0 cm along the left edge of the sternum about 3 mm, centering on the strongest point of the apex, and cutting the chest cavity into each layer of the chest cavity at a time. When choosing the electrocautery method, place the electrocautery electrode of the small high-frequency knife in the depth of the left front descending branch, let it solidify for 1-2 seconds, select the freezing method, and select the cylindrical steel pre-cooled (frozen) with liquid nitrogen nail. The head with a head diameter of 0.6 cm was quickly placed in the left coronary artery of the rat, and the myocardial area dominated by the upper 1/3 of the previous descending artery was frozen for 10 seconds. Observation of dynamic changes in ECG in two or more end leads, ST segment elevation (\→ 0.2 mV) and visually thin lesion areas and corresponding changes in the leads can be considered successful. I will. Close the chest cavity, pull out the ventilator, and handle the animal as needed.

　　[Features of the model] Compared with ligation, the operation is easier and the position is more accurate, and the complete coagulation/necrosis process of myocardial tissue and the formation of granulation/scar tissue can be accurately observed. Electrical stimulation can easily cause arrhythmia.

　　[Model evaluation and application] Both methods require opening the animal’s chest, but the complications are the same as the ligation method, and the mortality rate of the animal is still high. Both methods can cause myocardial infarction, and the changes of myocardial pathology and electrocardiogram are similar to those of clinical myocardial infarction patients, so they can be used for the research of myocardial injury and the treatment of myocardial infarction. However, these two methods are far from the etiology of patients with clinical myocardial infarction, and have very different physiological and biochemical indicators, so these differences should be used with caution.