动物造模,药效评价,动脉粥样硬化 z-bio 2024-09-19 378

　　(1) The reproduction method is to feed male experimental rabbits with a weight of about 2.0kg to induce diabetes. The feed contains 10% lard and 37% sucrose. Each animal consumes about 75g of feed every day. At the end of the 24th week, the animals were killed to observe atherosclerosis. The results showed that plasma glucose, insulin, total triacylglycerol (TG), total cholesterol (TC) and low-density lipoprotein (LDL-C) were significantly increased after the animals were fed with diet induced diabetes, and plasma glucose, TC and TG gradually showed a trend of continuous increase. Typical lipid streaks were observed in the aorta of experimental animals, with yellow stripes of varying lengths visible to the naked eye, slightly protruding from the surface of the endometrium. The percentage of lipid streak lesion area to the unfolded area of the aortic strip was (8.58 ± 1.35)%; Under the light microscope, the elastic plates of the animal's aorta and coronary artery walls were found to be broken, and the endothelial cells of the blood vessels were focal shedding. Many parts of the endothelial cells showed proliferative repair, presenting a multi-layered disorder; Under scanning electron microscopy, the arrangement of endothelial cells in animal blood vessels is disordered, the distance between cells is widened, the surface is rough, and there are many insect like changes. The damaged endothelial cell nuclei are exposed, and there are more blood cells adhering to them. Localized shedding of endothelial cells can also be seen, exposing the subendothelial elastic plate and a large amount of proliferative interstitial cells; Under transmission electron microscope, there were many myogenic foam cells in the aorta, smooth muscle cells migrated under the endothelium, and many monocytes adhered and migrated into the intima.

　　(2) The model features that a significant increase in plasma glucose concentration leads to an increase in blood viscosity, and high blood sugar can also generate superoxide stress, increasing the generation of oxygen free radicals and glycation end products (AGEs) in the body. Both can increase LDL modification and accelerate As formation. In the study of establishing an animal model of diabetes with As, rabbits as model animals are larger and easier to operate, which is superior to the hamster model induced by high-fat diet and intracavitary injection of STZ. At the same time, the composition of the feed used in this model is similar to the current diet characteristics of most countrymen, which is mainly sugar. Experimental animals also show typical insulin resistance characteristics and as lesions similar to those suffered by humans. This model is a good disease model to study the relationship between diabetes and As.

　　(3) The aorta of comparative medical model animals has typical lipid streaks, mainly distributed in the abdominal aorta, similar to the As prone area in humans; The rabbits used in the experiment are As susceptible animals and easy to operate; The diet used in the experiment to induce diabetes significantly increased the AS inducing factors of New Zealand rabbit plasma, such as TC, TG, LDL-C, Glu, Ins, etc. The changes of these indicators are basically similar to the common metabolic disorders (such as hyperglycemia, hyperinsulinemia, triacylglycerolemia) in type II diabetes patients.