| ObjectiveAtherosclerosis is an important disease threatened the health of people, and coronary atherosclerotic heart disease is one of its features, which was called coronary heart disease( CHD) in short. In Europe and America, 1/3 ~ 1/2 individuals died of CHD. In our country, its morbidity is increasing. Diabetes is a common disease at present. As more and more individuals suffered from it, researchers attached more importance to it. For diabetic patients, the risk of atherosclerosis is higher than non-diabetic individuals, the age of onset is younger, and its progress is faster. Epidemiological study found that 70% type 2 diabetic patients died of cardiovascular disease. Though the morbidity of cardiovascular disease in type 1 diabetic patients is lower than type 2 diabetes significantly, it is higher than non-diabetic individuals about 10%. Fatty liver is a common disease. Recently it was found that 15% patients could develop fibrosis and cirrhosis from pure fatty liver, and 3% would develop liver failure. The patients with type 2 diabetes or metabolism syndrome always associate with fatty liver, so some scholars proposed that fatty liver is a part of metabolism syndrome. Both of atherosclerosis and fatty liver come from the disturbance of lipid metabolism, thus the lipid metabolism in diabetes becomes one of the hotspots of research. At present, there are a few about anti- atherosclerotic factors, while there are many investigations about atherogenic factors. However, anti- atherosclerotic factors is equal to atherogenic factors in the protections and treatment of atherosclerosis. Finding out how to protect atherosclerosis becomes the new expectation.High density lipoprotein-cholesterol ( HDL-C ) is a well-known anti-atherosclerotic factor, which exerts the activity of anti-atherosclerosis through anti-oxidation and reverse cholesterol transportation. Epidemiological study showed thatthe improvement of HDL-C concentration could decrease the incidence of CHD events, the components of HDL which is affected by lipid metabolism determined its and- atherosclerotic effect, and lipid metabolism determines its components. Scavenger receptor Bl (SR-B1) is important in the metabolism of HDL-C. It is a receptor of HDL, which was discovered recently, and highly expressed in the liver, brush membrane of small intestine and atherosclerotic lesion, participating reverse cholesterol transportation-transporting the cholesterol from vascular wall and other tissues to liver, and then removing it with choler, so SR-Bl is known as a anti- atherosclerotic factor. Liver is the center of lipid metabolism, which produces and breakdowns various enzymes and receptors related to lipid metabolism, thus some scholars called atherosclerosis a kind of liver disease. Up to now, there isnt any report about the expression of SR-B1 in the liver of chronic diabetes. In this study, we measured serum lipid levels, pathology and lipid content of livers and the expression of SR-B1 in atherogenic diet induced atherosclerotic mice, STZ induced type 1 diabetic mice and high fat and high sugar diet induced type 2 diabetic mice, to investigate the relationship between SR-B1 and lipid metabolism in atherosclerosis and diabetes mellitus.Materials and methods1. Animals and dietsFemale C57BL/6J mice, 6 - 8weeks of age ( except type 1 diabetes group) , were purchased from experiment animal center in China Medical University. Mice were maintained in a temperature-controlled (25掳C) facility with a strict 12h light/dark cycle and were given free access to food and water.(1) Control group: Ten fed normal rodent chow pellets (4% fat, 24% protein, 4.5%crude fiber) for 16 weeks;(2) Atherogenic diet group: Five fed normal rodent chow pellets 8 weeks and then fed 8 weeks atherogenic diet(15%fat, primarily lard, 1.25% cholesterol and 0. 5% sodium cholate) for 8 weeks, were high fat and sugar diet group A, and ten fed atherogenic diet for 16weeks,were high fat and sugar diet groupB.(3) Type 1 diabetes group: Ten mice, 4weeks of ag...
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