Estrogen이 실험적 동맥경화증에 미치는 영향에 관한 연구 = An Experimental Study on the Effect of Estrogen upon Atherosclerosis of Lipid Fed Rabbits

다국어 초록 (Multilingual Abstract)

Atherosclerosis begins with the formation of atheroma within the intima having a core of lipid and a covering fibrous cap, and therefore, lipophage infiltrations are quite important in the atherogenesis. However, regarding the origin of lipophages, there are various opinions including theories of fibroblast, endothelial cell, monocyte or lymphocyte and muscle cell. The process of lipophage transformation is also controversial. And it is indicated that relevant treatment on this disease is a still symptomatic and conservative.
Concerning the relationship between sex hormone and atherosclerosis, Lorenz reported of the atherogenesis reinforced by diethylstylbesterol. In that while, others have noted that estrogen not only reduces the occurrence of atherosclerosis but also restrains atherosclerotic changes. Additionally, many studies argue that levels of serum cholesterol, phospholipid and triglyceride are increased, decreased or unchanged, when estrogen is administered.
This study is conducted to evaluate the effect of estrogen upon hyperlipidemia and atherosclerosis. Eighty healthy female rabbits weighing about 1.7kg have been used for the experiment and divided into 1) basic diet fed group (control), 2) lipid aministered group, 3) lipid ＋ estrogen administered group and 4) estrogen injected group.
The basic diet was composed of 70-80g bean residue, 100-250g vegetable and vegetable and 80-100g pellet diet per rabbit per day. The lipid diet was composed of basic diet plus cholesterol 500mg/kg, corn oil 1.5g/kg, bile salt 50mg/kg per rabbit per day. 20,000IU/kg of estrogen was injected to appropriate groups intramuscularly per rabbit per 3 days.
In doing this, aorta and coronary arteries have been examined grossly and microscopically, and the serum cholesterol, phospholipid, triglyceride levels and lipoprotein fractions in each rabbit have been also measured.
The results obtained from this study are as follows;
1. In the lipid administered group, sreum cholesterol, phospholipid, triglyceride, VLDL, LDL were increased and HDL decreased significantly. The aorta revealedvarious degree of atherosclerotic changes.
2. In the lipid and estrogen administered group, serum cholesterol, phospholipid, triglyceride were decreased and HDL increased apparently in the comparison of those in lipid administered group. Atherosclerotic changes were also obviously repressed.
3. In the estrogen administered group, no significant changes were noted.
The results obtained from this experiment indicates that 1) estrogen restrains atherosclerotic changes, 2) reduces abnormally elevated serum cholesterol, phospholipid, triglyceride, and 3) reinforces repressed HDL.