动物造模,肝硬化动物模型 z-bio 2022-02-05 599

　　(1) Replication method Adult male rats were injected intraperitoneally with 2 ml/kg body weight of 30% CCl4 paraffin oil solution twice a week for 7 weeks. Or, subcutaneously inject 40% CCL4 soybean oil solution 3 ml/kg body weight every 3 days, the initial dose is 5 ml/kg body weight, once every 3 days, a total of 14 times, and then feed 80% corn meal for the first 2 weeks at the beginning of the experiment , Use 20% lard mixture, mix 0.5% cholesterol with feed after two weeks, and use 30% ethanol as the only beverage within 42 days. Or, subcutaneous injection of 50% CCl4 soybean oil solution 3 ml/kg body weight, initial administration of 5 ml/kg body weight, change from day 5 to once every 4 days, intramuscular injection, a total of 15 times, drinking 10% ethanol during 60 Eat ordinary pellets continuously throughout the day instead of drinking water in it. Alternatively, 3-5 ml/kg body weight of 60% CCl4 mineral oil solution was injected subcutaneously every 4 days for a total of 15 times. The first 4 times weighed 5 ml/kg, and the 5-11 times weighed 3 ml/kg. 12 to 15 times the body weight is 5 ml/kg body weight, and 10% ethanol is used as the only drinking water for 10 consecutive days. The modeling process includes observing the general activities of the animals every day, weighing the animals every week, collecting whole blood to prepare serum after modeling, weighing liver tissues for biochemical tests, preparing homogenates of organs such as liver and spleen, and extracting organs. Measure organ coefficients and perform histological morphological examination.

　　(2) Model characteristics During the observation of the model, the model animals are sluggish, anorexia, lethargy, irritable bowel, and sometimes bite and attack, initially lose weight, and then gradually gain weight. Animals injected with 30% CCl4 solution intraperitoneally received serum alanine aminotransferase (ALT), total protein (TP), globulin (GLO), total cholesterol (TC), triacylglycerol (TG) and TC, TG , The content of L- is as shown in the figure. Hydroxyproline (HPA) in liver tissue was significantly increased, while serum albumin (ALB) content and albumin/globulin ratio (A/G) were significantly decreased. The liver tissues of all model animals appeared under an optical microscope. Fibrosis, most of which form pseudo-lobules. Under the electron microscope, the superstructure of liver cells of the model animals is obviously abnormal. The liver cells are swollen to varying degrees, some liver cell membranes are ruptured, the endoplasmic reticulum is expanded and destroyed, and there are a lot of lipids. There are some common areas in the sky. , That is, the electron density of mitochondrial matrix increases, the disappears, and neutrophils are more common in liver sinusoids. Subcutaneous injection of 40%, 50% and 60% CCl4 solutions for 42-66 days, the survival rate of animals is 46%-77%, and the success rate of liver cirrhosis model is 72%-100%. The normal liver tissue of adult animals is destroyed, and the original liver lobules are separated by a large number of proliferating fibrous tissues and wrapped into circles of various sizes to form pseudo-lobules. The arrangement of the hepatocyte cords in the pseudolobules is chaotic. There are no or deviated central veins in the lobules, or two or more central veins appear, and regenerated hepatocyte nodules are randomly placed, with large cell bodies, large nuclei and deep staining. Air bubbles and fatty degeneration occur.

　　(3) Comparative medicine CCl4 is the earliest and most widely used chemical substance that induces liver cirrhosis in animal models. CCl4 is activated by liver mitochondrial cytochrome P450 to produce carbon tetrachloride (CCl3). It attacks the phospholipids on the liver cell membrane structure, causing lipid peroxidation and destroying the cell membrane structure. CCl3 also forms a shared relationship with intracellular proteins. It damages mitochondria, reduces the production of reductase A (NADH) and adenosine triphosphate (ATP) in the liver, inhibits fatty acid oxidation, affects the tricarboxylic acid cycle, and "suffocates" liver cells, causing me to die. Even the deformation and destruction of the Golgi apparatus and cell membranes can lead to impaired protein synthesis, energy metabolism and lipid oxidation. Triacylglycerols and fatty acids accumulate in liver cells, leading to steatosis, liver cell necrosis and fibrosis. High concentrations of CCl4 mainly affect the central nervous system. Repeated use of low concentrations can damage the liver and kidneys. Repair of liver damage will eventually lead to liver cirrhosis. CCl4 is used to induce liver cirrhosis models, usually at a concentration of 30% to 60% as a model solution, rats are used as model objects, subcutaneously or intraperitoneally injected, tube feeding, steam inhalation or animals. Among them, subcutaneous injection is the most commonly used method, but due to its rapid absorption into the systemic circulation, subcutaneous injection is more toxic to the brain and kidneys, and the injection site is invasive abscesses and ulcers, and the mortality rate is as high as 30 years. % To 40%; due to the high concentration of intraperitoneal injection into the portal vein, the model formation time is short, but the animal mortality rate is still high (20% to 35%). Gastrointestinal nutrition can be carried out directly. Although CCl4 is absorbed by the liver, it has a great gastrointestinal reaction and can easily damage the esophagus. Although vapor inhalation is absorbed quickly, it is highly irritating to the respiratory tract, highly toxic to the central nervous system, and cannot tolerate animals. The mixed feeding method can dissolve the moldant in a small amount of food. Due to its rapid oral intake, it is possible to control the concentration and reduce or reduce the diet. Although this is a stimulus to the digestive tract, it is difficult to grasp the actual intake due to the influence of animal appetite, the experiment period is long, and the end point is unclear.