Method of establishment of model of experimental atherosclerosis in rats

Objective:To establish an experimental method for atherosclerosis model of rats. Methods:Thirty Sprague-Dawley rats were divided into two groups randomly: control group(n=10) and model group(n=20).Control group fed with normal food, Model group fed with high cholesterol diet(1% cholesterol; 0.5% sodium cholate; 0.1% methimazole;5%lard) after intraperitoneal vitamin D3 (700,000 IU/kg, commonly four times at interval of two days) injection. Serum lipid and morphological change of aorta were determined after 2 months. Results: The levels of serum total cholesterol, low density lipoprotein (LDL) and triglyceride (TG) in model group were significantly higher than those in control group (P0.01). The levels of high density lipoprotein(HDL) were obviously lower than those in control group(P0.05). Compared with control group. There were serious calcification,irregularly thickening, disorganized fibers of vascular smooth muscle and some deposited foam cells in the tunica media of aorta under light microscope in the control group. Marked increase of disordered collagen local fiberous lysis and degeneration could be seen under electron microscope. Some lipid particles deposited among extracellular space, pycnosised and heavily stained nuclei of vascular smooth cells that even necrosed somewhere and vacuolated mitochondrions in some of them could be observed. Endothelial cell shedding, thrombosis and foam cell formation could also be observed. Conclusion: Rat can be used as a ideal model for research of atherosclerosis created by high cholesterol diet plus vitamin D3 overload.