动物模型 z-bo 2020-07-30 651

　　[Simulation mechanism] Thrombus is formed in the peripheral blood vessels, the emboli flow through the blood and reach the pulmonary artery, blocking the pulmonary artery and forming an embolus.

　　[Modeling method]

　　1. After the animal is anesthetized with the Nowak procedure, loosen the side of the jugular vein and the common carotid artery, arterial cannula and venous cannula. The arterial cannula and the venous cannula are connected by a three-way tube, and the other end of the three-way tube is connected by a 1 ml syringe. When connected, the syringe will draw 0.6 ml of thrombin (10IH thrombin U/ml) as well as the arterial cannula and syringe. Open the channel between them, let the blood flow into the 1ml syringe, close the channel, take out the syringe and shake it several times to make it. Thoroughly mix thrombin and blood, and then inject the blood after thrombin treatment into the jugular vein from the tee. Please note that the jugular vein should be clamped for 10 minutes at this time. When a clot forms, remove the vein clip to release the embolus. Emboli follow the blood flow to the pulmonary artery, forming a pulmonary embolism model.

　　2. Using I-labeled fibrinogen commonly used in the iodine labeling method (rhodogen method), 125I-containing fibrinogen and thrombin are mixed to form a 125I-labeled blood clot, which is then injected into the animal. Metamorphism is usually used for marking. The specific steps are as follows: take the Lodogen solution, dissolve it in chloroform, dry it with nitrogen at room temperature to make a reaction tube, add the fibrin solution, immediately add Na125I11.1x10Bq, shake well and mix the label on the gel column The reaction mixture. plus. Chromatographic deiodination, phosphate buffer elution. Save the labeled fibrinogen peak eluate and store it at -20°C for future use, and control the specific activity to about 2.78 x 10 Bq/mg to ensure fibrin thrombin activity. Next, 125 I fibrinogen, CaCl2 and human thrombin were sequentially added to fresh human whole blood anticoagulated with sodium citrate. Aspirate the mixture quickly, mix it evenly in a polyethylene test tube, and then incubate at 37°C for 20 minutes to form a 125I test strip in the test tube. Transfer the thrombus into an Erlenmeyer flask and shake it with saline and rinse it. After washing, the 125 I thrombus was cut into equal length strips, and the radioactivity was measured and recorded respectively.

　　[Model Features] Due to the rabbit's medium size, low price, convenient feeding, high reproduction rate and survival rate, and obedience to temperament, the rabbit fibrinolytic system is more humane than other experimental animals. It is close to the melting system. Rabbit pulmonary embolism is the most mature, common and ideal animal model. The dog pulmonary embolism model can maintain a high average pulmonary artery pressure and pulmonary vascular resistance within 4 hours after embolization. After thrombolysis in this model, the average pulmonary artery pressure and pulmonary vascular resistance will appear after 30 minutes and begin to decrease significantly. This is consistent with the clinical manifestations of patients with pulmonary embolism and is a very ideal model.. In addition, Dogs are rich in blood and can tolerate a variety of blood tests, avoiding cardiovascular changes caused by simple blood tests. [Evaluation and application of the model] Since this method is mainly a method of forming a blood clot outside the body and injecting it into the body, compared with humans, when a pulmonary embolism is formed, the imbalance of the blood coagulation mechanism is the reason that it is usually hypercoagulable. And this model cannot reflect the hypercoagulability of the human body. Therefore, there are still disadvantages. When a dog is used to create a model, the dog will become a large individual, with a lively personality, a strong attack on unfamiliar experimenters, a certain risk and relatively expensive expenses. This is mainly due to the more complicated research?