动物造模,肝衰竭动物模型,急性肝缺血 z-bio 2021-11-29 385

　　(1) Model method Fix the adult under anesthesia, open the abdomen along the midline of the abdomen, and suture the inferior vena cava above the renal vein with a 5-0 vascular suture method. After finding the portal vein at the bottom of the mesentery, release it from the hepatic portal vein to the height of the splenic vein and ligate and cut the collateral branches of the portal vein. Heparin was injected intravenously at 100 U/kg body weight. Clamp the portal vein at the level of the splenic vein, then clamp under the fork of the portal vein part of the hepatic vein, cut and ligate. Insert the shunt tube containing the anticoagulant into the portal vein and above the level of the splenic vein, ligate and fix, insert the inferior vena cava upward through the capsular bag, and suture the capsular bag sutures. Before inserting the inferior vena cava, a non-invasive vascular clamp is used to block the blood flow in the inferior vena cava above and below the suture. Release the common bile duct from the hepatoduodenal ligament, and then ligate the hepatoduodenal ligament near the duodenum, blocking all hepatic arteries. Optionally, after opening the abdomen, release the portal vein and the inferior vena cava, perform end-to-end or left-to-right anastomosis of the portal vein and the inferior vena cava, and close the hepatic artery based on this. Rats can use vascular clamps to temporarily clamp the hepatic artery directly, and experimental dogs or pigs can perform a second operation 24 hours after the portal vein anastomosis to temporarily clamp the hepatic artery 4-6 times, which can be clamped in time. Through the modeling and experiment process, the animal's blood pressure, pulse and consciousness are continuously observed, and the time of death is recorded. At the same time, blood is dynamically collected to prepare serum and liver tissue for liver function testing. . Perform morphological examination.

　　(2) Model characteristics: After 30-60 minutes of completely blocking the blood flow to the liver, the animal begins to become restless and gradually becomes hepatic coma. The systolic blood pressure gradually decreased over time, and all animals died within 75-155 hours. The liver of a dead animal was dark red, dull, and scattered with purple spots. Due to the obstruction of liver blood supply, animal serum ALT, AST, LDH, NH3 gradually increased, PT gradually increased, while fibrinogen (FIB) and GLU gradually decreased. Two hours after the hepatic blood flow was blocked, microscopic examination revealed that the intervertebral disc space was significantly enlarged, the central vein collapsed, intrahepatic vacuolar degeneration occurred, the nucleus was difficult to digest, the nucleoli disappeared, and the glycogen particles in the cytoplasm were homogeneous and rough. Degranulation of facial cytoplasmic reticulum, mitochondrial edema, partial dissolution, nuclear chromatin accumulation, nuclear malformation, formation of pseudo-inclusion bodies in the nucleus; liver failure, hepatocyte dislocation, liver plate peeling, local appearance and spotted hepatocyte necrosis.

　　(3) Comparative medicine The acute liver ischemia model is currently an ideal animal model for inducing acute liver failure. Its surgical steps include portal vein vena cava anastomosis and donor hepatic artery ligation. Among them, the donor hepatic artery ligation involves two methods: complete ligation and temporary clamp. The former refers to the complete clamping or ligation of the portal vein and hepatic artery, and the latter refers to the complete blood supply block model. The death time of this model animal is usually short, has similar characteristics to the liver resection model, and is irreversible, so it is only suitable for short-term evaluation of in vitro bioartificial liver support systems or intracranial pressure studies. Changes in cerebral edema and cerebral edema associated with acute liver failure. In the latter, after the portal vein vena cava anastomosis, the hepatic blood vessels are temporarily clamped by pulling the clamp or the suspension wire, which causes liver failure due to acute liver ischemia, and then releases the liver and restores the liver blood supply. The latter has a significant correlation between the degree of acute liver failure and mortality, because the interval between anastomosis and hepatic artery ligation determines the number of collateral circulation. Therefore, the time interval between anastomosis and hepatic artery ligation is critical. Model preparation. This model is potentially reversible and is suitable for long-term bioartificial liver support experiments and observations. Currently, most bioartificial liver animal experiments use this method, which is currently the most ideal surgical model.