Effect of Estrogen Replacement Therapy on the Serum Nitric Oxide and Endothelin-1 Level of Ovariectomized Rats

Abstract

Objective To investigate the effects of estrogen replacement therapy on the serum nitric oxide and endothelin-1 level of ovariectomized rat.Methods The ovariectomized animal model and estrogen replacement therapy rat were established,thirty female rats were randomly divided into three groups:group A,ovariectomy;group B,ovariectomy plus estrogen replacement therapy;group C,sham-ovariectomy.The rats were killed after two months.The serum nitric oxide and endothelin-1 level were determined.Results In group A,the serum nitric oxide level was lower as compared with group C,but the serum endothelin-1 level was higher than those in group C.In group B,the serum nitric oxide level was higher and the serum endothelin-1 level was lower than those in group A.Conclusions Estrogen could modulate the productions of the nitric oxide and the endothelin-1 in the vascular endotheliocytes and improve the function of the vascular endothelial cells,which may be a bases of the benificial effect of estrogen in the prevention of atherosclerosis.