Regulation of estrogen receptor beta mRNA in the brain: opposite effects of 17β-estradiol and the phytoestrogen, coumestrol

摘要: Estrogen receptor alpha (ERα) and estrogen beta (ERβ) are differentially distributed in the brain likely mediate different estrogen-dependent processes. ERβ is abundant bed nucleus of stria terminalis, medial preoptic nucleus, paraventricular hypothalamus amygdala rat. In which devoid ERα, colocalized with neuropeptides, oxytocin vasopressin, suggesting a potential functional role for regulation these peptides. We examined mRNA expression rat by 17β-estradiol phytoestrogen, coumestrol. 17β-Estradiol treatment decreased situ hybridization signal 44.5% (PVN), but had no effect terminalis (BnST) or (MPA). contrast, dietary exposure to coumestrol increased 47.5% PVN BnST MPA. These data demonstrate that like down regulated region specific manner brain. Furthermore, may modulate ERβ-dependent processes acting as an anti-estrogen at ERβ. This contradicts results from cell transfection assays suggest estrogenic activity on ERβ, indicating mode action be tissue specific, metabolism alter its effects. Because highest concentrations phytoestrogens found legumes, vegetables grains, they most prevalent vegetarian traditional Asian diets. Understanding neuroendocrine effects particularly important now being marketed natural alternative replacement therapy sold highly concentrated pills powders.