动物造模,药效评价,Lieber-Decarli模型 z-bio 2024-09-02 398

　　(1) The replication method was used to feed rats with liquid food containing only complete nutrients and alcohol daily. This food is prepared according to calories, including 18% protein, 21% fat, 47% sugar (with 36% of calories replaced by alcohol), as well as some vitamins and inorganic salts. After 4 weeks, whole blood was extracted to prepare serum for serum biochemical testing, and the liver was removed for histological examination. Alternatively, a certain amount of pyrazole can be added on top of alcohol liquid food, or endotoxin can be intravenously injected while feeding ethanol liquid food. Biochemical and pathological examinations can be conducted as described above several weeks later.

　　(2) Model characteristics: Rats in the same litter were fed a liquid diet containing complete nutrients and ethanol on a daily basis. After 4 weeks, significant hepatic steatosis was observed, but there was no occurrence of alcoholic hepatitis or fibrous tissue hyperplasia. Feeding rats with ethanol liquid feed containing pyrazole (2mmol/L) resulted in liver steatosis, monocyte infiltration, and hepatocyte necrosis after 12 weeks. In addition, thickening of the central vein of the liver, severe ballooning of surrounding cells, fibrosis of the central vein and liver cells were also observed, with alcoholic hepatitis being the main lesion. After feeding ethanol liquid food, rats were injected with 2mg/kg body weight of endotoxin through the tail vein. In addition to pathological changes in alcoholic hepatitis, rats also showed extrahepatic manifestations such as complement activation, platelet hyperfunction, and microcirculation disorders.

　　(3) There is no doubt in comparative medicine that the occurrence and development of alcoholic liver disease are closely related to the concentration, dosage, and cycle of ethanol intake by the body. The key issue of using rats to replicate an experimental animal model of alcoholic liver disease is to solve the problem of rats' aversion to ethanol and the potential nutritional disorders caused by long-term ethanol intake. Feeding rats with liquid feed containing total nutrients and ethanol invented by Lieber Decarli et al. not only maintains their long-term intake of sufficient ethanol and high blood ethanol concentration, but also provides sufficient total nutrition to ensure that the rats are in a good nutritional state. Research has confirmed that the severity of alcoholic fatty liver disease is related to the fat content in liquid food, with 25% calorie fat being the minimum proportion of fat in liquid food. Because dietary fat is an important source of triglycerides accumulated in alcoholic fatty liver disease. Pyrazole is an alcohol dehydrogenase (ADH) inhibitor. When it is infused into animals together with alcohol, pyrazole can inhibit the ADH metabolic system, enhance non ADH system metabolism, and produce acetaldehyde metabolism through the latter pathway slower than the former. Therefore, the increased acetaldehyde can inhibit the microtubule assembly and protein secretion of liver cells, leading to liver cell necrosis and creating a more severe or close to human alcoholic liver injury animal model. As for the study of the appropriate dosage of pyrazole in this model, there have been no reports so far. Alcoholic hepatitis or cirrhosis in humans is often accompanied by endotoxemia. After feeding rats with ethanol liquid food and intravenous injection of endotoxins, there are many similarities between the pathological changes and extrahepatic features of liver tissue and clinical manifestations, making it a good model for studying endotoxemia in alcoholic liver disease. In fact, some researchers have changed the experimental animal subjects of the Lieber Decarli model to baboons. Liquid food is prepared by calories as follows: 18% protein, 21% fat, and 61% carbohydrates (50% of which are replaced by ethanol). Due to baboons' preference for alcohol, feeding this liquid food for 1-3 years resulted in one-third of the animals developing alcoholic liver cirrhosis. Although this model is very similar to human alcoholic liver cirrhosis, it is difficult to promote its application due to the expensive experimental animals and long experimental period. So far, there have been no reports of its application in China.