Estradiol inhibits endothelin-1 synthesis, an effect that may contribute to the cardiovascular protective effects of estradiol. Recent findings that estradiol inhibits neointima formation in mice lacking estrogen receptors suggests that the cardiovascular protective effects of estradiol may be mediated by means of an estrogen receptor-independent mechanism. Because 2-hydroxyestradiol and 2-meth...

The brain synthesizes steroids de novo, especially progesterone. Recently estradiol has been shown to stimulate progesterone synthesis in the hypothalamus and enriched astrocyte cultures derived from neonatal cortex. Estradiol-induced hypothalamic progesterone has been implicated in the control of the LH surge. The present studies were undertaken to determine whether hypothalamic astrocytes der...

The calf uterine estrogen receptor showed positive cooperativity of [3H]estradiol equilibrium binding; the Scatchard plot was convex and the Hill coefficient was 1.69 +/- 0.021 (n = 14). The effects of the estrogenic antagonists, zuclomiphene (cis-2-(p-[2-chloro-1,2-diphenylvinyl]phenoxy)triethylamine citrate) and enclomiphene (trans-23-(p-[2-chloro-1,2-diphenylvinyl]phenoxy)triethylamine citra...

We tested the hypothesis that estrogen acutely stimulates constitutive NO synthase (cNOS) activity in human peripheral monocytes by acting on an estrogen surface receptor. NO release was measured in real time with an amperometric probe. 17beta-estradiol exposure to monocytes stimulated NO release within seconds in a concentration-dependent manner, whereas 17alpha-estradiol had no effect. 17beta...

The steroid 17β-estradiol has emerged as having both beneficial and detrimental effects in relation to cardiovascular physiology. To provide clarity on the effect of 17β-estradiol on atherogenic process, we examined its regulatory role in LDL-receptor expression in macrophages. We determined if the previously reported 17β-estradiol-mediated reactive oxygen species (ROS) generation in macrophage...

Systemic estradiol treatment enhances hippocampus-dependent memory in ovariectomized rats. Although these enhancements are traditionally thought to be due to circulating estradiol, recent data suggest these changes are brought on by hippocampus-derived estradiol, the synthesis of which depends on gonadotropin-releasing hormone (GnRH) activity. The goal of the current work is to test the hypothe...

We previously demonstrated that estradiol administered in viva elevates the number of a,-adrenoceptors in preoptic area (POA) and hypothalamic membranes from ovariectomized female rats and potentiates a, receptor augmentation of ,&adrenoceptor-stimulated CAMP formation in slices from these brain regions. Present studies examined (1) if estradiol selectively regulates any cY,-adrenoceptor subtyp...

Feminization in men occurs when the effective ratio of androgen to estrogen is lowered. Since sufficient estrogen is produced in normal men to induce breast enlargement in the absence of adequate amounts of circulating androgens, it has been generally assumed that androgens exert an antiestrogenic action to prevent feminization in normal men. We examined the mechanisms of this effect of androge...

Introduction: The nucleus paragigantocellularis lateralis (LPGi) is involved in the descending pain modulation. The neurostreoid, 17β-estradiol found in the PGi nucleus and modulates nociception by binding to estrogen receptors and also by allosteric interaction with NMDA receptors. In this study, the role of NMDA receptors in the 17β-estradiol-induced pain modulation was investig...

We have used an immunoperoxidase technique utilizing a monoclonal antibody to the estradiol receptor to identify immunoreactive estradici receptor in breast carcinomas and have examined the relationship be tween the immunoreactive estradiol receptor and response to therapy in patients with advanced breast cancer. Fifty-six patients were found to be assessable for response to endocrine therapy. ...