动物模型,动脉粥样硬化 z-bo 2020-08-06 560

　　(1) Copy method Male experimental rabbits weighing 2.0～2.5kg. After 15 days of adaptive feeding, they were fed with high methionine feed (1% methionine was added to the standard rabbit feed) for 8 weeks. The detection indicators include blood lipids and serum total homocysteine (the normal range is 6.14～10.74μmol/L, the upper limit of this value is defined as rabbit hyperhomocysteinemia). Animals underwent abdominal aortic vascular ultrasound examination every 4 weeks to indirectly determine the degree of abdominal aortic stenosis and the formation of aortic plaque. Lumen stenosis degree at n weeks = [(Lumen inner diameter at 0 week-lumen inner diameter at n week)/Lumen inner diameter at 0 week]×100%. At 8 weeks, the animals were sacrificed by bleeding from the femoral artery, and the artery from the aortic arch to the branch of the iliac artery was taken longitudinally and fixed with 10% formaldehyde to calculate the percentage of atherosclerotic plaque in each aorta. Homocysteine (HCY) of homomethionine rats increased significantly from 4 weeks (concentration greater than or equal to 10.74μmol/L). At the 8th week, the degree of lumen stenosis increased significantly; the abdominal aorta and the bifurcation of the iliac artery were both visible and thickened in the intima, with light yellow plaques, and the percentage of aortic plaque area was significantly increased. Obvious plaques can be seen below the lumen.

　　(2) Features of the model This model is made of rabbits and is more sensitive to As. At the same time, the HCY concentration was measured in different experimental periods to observe the time of hyperHCYemia and the effect of early hyperHCYemia on the formation of atherosclerosis. This model is made with a high-methionine diet. The resulting atherosclerosis model is lighter and slower than the high-fat diet, but it is helpful to explore the different pathogenesis of As.

　　(3) Comparing the medical hyperlipidemia model with the high methionine model, the former forms atherosclerosis faster (only 4 weeks), and the degree is heavier (the naked eye has more atherosclerotic plaques and blood vessels during autopsy. The degree of stenosis is severe). The results of this model showed that after 4 weeks of high methionine diet, obvious hyperHCY had formed (exceeding the upper limit of the 95% normal range), but the abdominal aortic ultrasound examination had no obvious indirect changes such as luminal stenosis, to obvious There is still a certain period of time for the formation of As, which is suitable for studying the relationship between hyperHCYemia and As formation and development, and the significance of early detection of hyperHCYemia and correction to delay or prevent the formation of atherosclerosis.