The Expression of Estrogen Receptor is Dependent on the Estrogen Level and Associated with Cholesterol - Rich Diet in Female Rat's Heart and Vascular Endothelial Cells

摘要

Objective To study the effects of estrogen level and cholesterol - rich diet on the expression of estrogen receptor (ER) in cardiovascular tissues including vascular endothelial cells (VEC) of female rats. Methods The receptor binding assay (RBA) was adopted to measure the estrogen receptor level in aortic wall, heart and vascular endothelial cells of female rats on a cholesterol - rich diet. A radioimmunoassay was employed to measure the level of serum estradiol. Results The number of ER significantly decreased in hearts, aorta and vascular endothelial cells in the ovariectomized rats and the rats on a cholesterol- rich diet. In contrast, the adminis-tration of estrogen somewhat restored the expression of ER. Conclusions For female rats, the level of estrogen affects the expression of ER in cardiovascular system. The number of ER decreases along with the decrease in the level of estrogen. A cholesterol -rich diet also can decrease the expression of ER in cardio-vascular system of female rats.