疾病动物模型,心肌炎模型 z-bio 2021-03-17 340

　　(1) Replication method SPF male BALB/c mice aged 4 weeks, weighing 10-12 g, keep the air in a fresh room, the temperature is (20±4) °C, and the relative humidity is 60%. 100,000 pfu CVB3 (Nancy strain, MCMV suspension) was injected intraperitoneally at a volume of 0.1 ml/mouse. 7 or 14 days after modeling, the mice were subjected to a limb-guided electrocardiogram. Standard leads I and II. Then, the mouse's eyeballs were removed and blood was collected. After clotting the blood sample, centrifuge the supernatant and store the supernatant in a refrigerator at -70°C for later use. The animal was decapitated and the chest cavity was opened. For general observation of the heart, the heart is removed and weighed (HW) to calculate body weight/body weight (HW/BW). The heart was aseptically removed and cut into two parts for virus titration and histopathological examination. The left half of the heart was fixed with 10% formaldehyde and embedded in paraffin. The slice thickness was 4 μm and the interval was 100 μm. Each sample was cut into 5 pieces, inspected under an optical microscope, scored and averaged. .. If a mouse that died of natural causes is found during autopsy, weigh (BW) (BW), perform autopsy, calculate HW/BW, and fix the left half of the heart with 10% formaldehyde within 2 days. carry out. Time of death.

　　(2) Model characteristics MCMV suspension infected mice have epicardial hemorrhage under the pericardium. A total of 44.5% of infected mice have white spots, bands and patchy lesions, and myocardial slices have no obvious abnormalities. . Some infected mice that died of natural causes showed lamellar necrosis and pulmonary hemorrhage. On the 7th day, myocardial cells appeared swelling, local granular degeneration, a small amount of epicardial lymphocyte infiltration and a large number of local infiltration of surrounding inflammatory cells; medium-sized spheroids; impetigo and lysis of a single myocardial cell nucleus, local necrosis was small in the first Atrophy of cardiomyocytes and infiltration of monocytes and lymphocytes were observed on the 14th day; it started and remitted on the 14th day; the calculation of the cardiomyopathy score showed that they were all ≤ 2 grade. This is a mild change of myocarditis. The mouse ECG changes up to 50%, the main changes are partial P wave inversion, abnormal Q wave, premature ventricular contraction of the atria and ventricles, sinoatrial block, 2:1 to 4:1 atrioventricular block, etc. The incidence of myocarditis in mice was 69.4%, the peak mortality rate after infection was 7-14 days, and the mortality rate was 11.11%. The model has excellent repeatability and stability, and the effect is sufficient.

　　(3) Comparative medicine HCMV is an important virulence factor for fetuses, newborns, adults, and immunocompromised individuals (organ transplant recipients, malignant tumors after radiotherapy, chemotherapy, AIDS patients, etc.). MCMV and HCMV have many similarities at the gene and nucleic acid level, and the human gene analogues present in HCMV are also present in MCMV. The changes in humans and mice caused by MCMV and HCMV infections are very similar. The disease is mainly monocyte infiltration, accompanied by cardiomyocyte necrosis and P wave inversion, abnormal Q wave, premature contraction of atria and ventricles, sinus obstruction 2:1, 4:1 atrioventricular block and other changes. It provides an excellent model for studying its etiology and observing the effects of drugs that inhibit MCMV.