The effects of ovariectomy and cholesterol rich diet on the content of estrogen receptor in vascular endothelial cells and hearts of female rats

Objective To investigate the effects of ovariectomy and cholesterol rich diet on the change of estrogen receptor content of vascular endothelial cells and hearts of female rats. Methods The receptor binding assay (RBA) was adopted to measure the content of estrogen receptors, and the serum levels of estradiol and lipids were measured. Results The content of ER was much lower in hearts and VEC of ovariectomy〔(0.51±0.09) fmol/mg pro,(6.73 ± 0.52) fmol/106 cell〕and cholesterol rich rats〔(0.97±0.12) fmol/mg pro,(9.15 ±0.53) fmol/106 cell〕than pseudo-operation rats 〔(2.08±0.15) fmol/mg pro ,(17.66±1.26) fmol/106 cell , P0.01〕, but more apparently at the group of ovariectomy. Given estrogen for nine weeks, the content of ER was improved〔(1.75±0.28) fmol/mg pro,(13.81±1.06) fmol/106 cell〕. Serum level of estradiol dereased 〔(181±36) pmol/L vs.(1 004±88) pmol/L, P0.01〕 and serum cholesterol level increased 〔(1.84±1.27) mmol/l,(1.22±0.11) mmol/l, P0.01〕 significantly after the ovaries of female rats were resected. Conclusions The content of ER in VEC and hearts are affected by serum estrogen level, and cholesterol rich diet decrease the content of ER remarkably.