Expression of estrogen receptors in the coronary arteries of young and premenopausal women in relation to central obesity.

Abstract

To examine the relationship of coronary estrogen receptor (ER) expression with atherosclerotic lesions and central fat accumulation in premenopausal women. A total of 52 female forensic autopsy cases aged between 18 and 49 y. Height, body weight and waist and hip circumferences were measured and body mass index (BMI) and waist-to-hip ratio (WHR) were calculated. Intima thickness or maximal thickness of the plaque were measured from samples taken from the left anterior descending artery (LAD). Macrophage infiltration and smooth muscle cells were localized by immunostaining. ER was detected immunohistochemically and by Western blot analysis, and the ER immunopositive area in the intima was measured. ER immunoreactivity was observed in the intima in 60% of the samples, and it was most intense in the advanced plaques near the lipid core next to the maximal intensity of macrophage staining. The ER immunopositive area had a significant positive correlation with LAD intima thickness, which in turn was significantly correlated with waist circumference and WHR when adjusted for age and BMI. Premenopausal women with the central type of fat accumulation have advanced coronary plaques in which ER expression is localized near the lipid-rich and macrophage-rich zone. The higher expression of ER in the arterial plaques may represent a compensatory mechanism against atherosclerosis.