The Impact Of Soy Isoflavones In Ovariectomized Rats Lipid Metabolism And Arterial Endothelial Function

[Objectives] This study is to investigate the effect of soybean isoflavone on the lipids metabolism and arterial endothelium function in ovariectomized female rats.[Methods] Fifty Sprague-Dawlery female rats, two months old, were randomly assigned to five groups : A(sham operated); B(ovariectomized and hyperlipid food); C(OVX and hyperlipid food and 20mg · kgbw-1· d-1 soybean isoflavone); D(OVX and hyperlipid and 60mg · kgbw"1· d-1 soybean isoflavone); E(OVX and hyperlipid and 180mg·kgbw-1· d-1 soybean isoflavone). Beginning from 7 days after surgery, the rats were treated intragastrically with soybean isoflavone or solvent once daily respectively for a period of 60 days. Serum TC, TG, HDL-cholesterol, LDL-cholesterol, SOD, MDA, NO(nitric oxide) et al were measured. At the end of the experiments, endothelium-mediated arterial dilation were also evaluated.[Results] B group had a significant increased in serum TC, TG, LDL-C, AI(atherosclerosis index ), MDA% liver index and TG, MDA of liver, decreased NO, SOD of serum than other groups (P<0.05) ; HDL-C contents were significant increased in C, D and E groups than that in B group (P<0.05); Moreover, soybean isoflavone cound improve the endothelium-mediated arterial dilation of ovariectomized female rats.[Conclusions] Soybean isoflavone can not only decreased TG ^ TC -, LDL-C, but also increased HDL-C. Soybean isoflavone can inhibit the process of lipid superoxide formation and improve the endothelium-mediated arterial dilation of ovariectomized female rats.