Factors associated with estrogen receptors-alpha (ER-alpha) and -beta (ER-beta) and progesterone receptor abundance in obese and non obese pre- and post-menopausal women.

There is scarce information about the factors associated with estrogen receptors (ER) at menopause. In 113 volunteers pre- and post-menopausal healthy women, grouped as with and without obesity, estrogen receptors-alpha and -beta, and progesterone receptor (PR) were measured by immunohistochemistry in skin punch biopsies obtained from the external gluteal area. In pre-menopausal women, biopsies and a blood sample were performed between days 7 and 14 of the cycle. Serum hormone levels were measured by immunoradiometric assay or radioimmunoassay. After menopause, ER and PR amounts decreased significantly. At pre-menopause, obese women had lower PR levels than non obese (P<.006). In the post-menopausal group, obese women showed higher ER-alpha (P<.03) and ER-beta (P<.02) levels than the non obese group. In the analysis of factors associated with the amount of steroid receptors for the total group, log[ER-alpha], log[ER-beta], and log[PR] were associated with age (P<.002, <.005, and <.004, respectively). The log[ER-alpha] was also associated with log[FSH] (P<.0008); meanwhile, the log[PR] showed a marginal correlation with log[FSH]. In pre-menopausal women no factor associated with any of the three receptors was found. In post-menopausal women log[ER-alpha] was associated with log[estrone] and log[DHEAS] (P<.003 and <.02, respectively). log[PR] was associated with BMI (P<.002), years since menopause (P<.05), and log[DHEAS] (P<.003). We concluded that ER and PR diminish sharply at post-menopause. At this stage the amount of receptors depends on several factors such as BMI, years since menopause, and androgen precursors.