动物模型,细菌感染 z-bo 2020-08-07 498

　　(1) Method of replication: Rabbits, male or female, weighing 2～3kg, sheared and sterilized, spread sterile towels, make 3～4 abdomen incisions under the xiphoid process, expose and separate the common bile duct, and insert diameter l outside the common bile duct. mm sterile plastic tube, ligated with No. 1 wire and pulled out the plastic tube to cause partial stenosis of the common bile duct. Expose the gallbladder again, insert a needle into the body of the gallbladder, inject 0.1ml of Escherichia coli bacteria liquid with a concentration of 1×100000/ml, ligate the needle port, close the abdominal cavity and complete the modeling. 15 days later, blood was collected from the heart and serum was prepared for serum biochemical testing; the rabbits were sacrificed, the liver and gallbladder were dissected, the bile was extracted to check for stone particles or crystals under a low-power microscope, and the gallbladder was opened to visually check the stones, and the liver and gallbladder were placed Fix in 10% formaldehyde solution and use light microscopy technique for histological examination.

　　(2) Characteristics of the model: Partial stenosis of the common bile duct and injection of E. coli into the gallbladder were performed. The model rabbits showed listlessness, hunched back, loose and dull hair, slow movement, thin appearance, reduced food consumption, and scrotum. Effusion, serum biochemical examination showed that β-endorphin (β-EP) decreased, tumor necrosis factor-a (TNF-a), substance P (SP), γ-glutamyl transpeptidase (γ-GT) , Alkaline phosphatase (ALP), total bilirubin (TBIL), conjugated bilirubin (DBIL) increased. Pathological examination showed liver enlargement, multifocal cholestasis, multiple liver abscesses, severe inflammation and liver necrosis, a large number of liver and bile duct stones; gallbladder enlargement was more obvious, cyst wall mucosa ulcer, necrosis, and submucosal fibrous tissue proliferation . This model is characterized by a high rate of stone formation, the stones are massive or flakes, yellow-green or brown-green in color, soft and fragile, and may be bile pigment stones or mixed stones. The biggest shortcoming of this model is the higher mortality rate.

　　(3) Comparative medicine Human cholecystitis is mostly caused by bacteria, and cholestasis is often the basis of the disease. This model uses partial stenosis of the common bile duct to cause bile stasis. Changes in the physical and chemical properties of bile during cholestasis can induce the formation of stones in the bile. The latter stimulates the bile duct and damages the mucosa, making the injected E. coli more easily invaded, resulting in congestion and edema of the cyst wall mucosa. Epithelial cells were degenerated, necrotic, and shed, and the wall showed varying degrees of neutrophil infiltration. Compared with the simple bacterial bile duct infection model, this model is characterized by bile duct bile stasis, formation of biliary stones and high stone formation rate, which is closer to the clinic.