BACKGROUND Estrogen is cardioprotective of the coronary circulation by mechanisms incompletely understood. This study determined the effect of chronic 17beta-estradiol replacement on dilator responses to acetylcholine and sodium nitroprusside of the isolated coronary microcirculation. METHODS AND RESULTS Adult female guinea pigs were ovariectomized, and a 21-day-release pellet containing 0.0,...

Background—Estrogen is cardioprotective of the coronary circulation by mechanisms incompletely understood. This study determined the effect of chronic 17b-estradiol replacement on dilator responses to acetylcholine and sodium nitroprusside of the isolated coronary microcirculation. Methods and Results—Adult female guinea pigs were ovariectomized, and a 21-day-release pellet containing 0.0, 0.1,...

Estrogens have an important role in regulating detrusor smooth muscle (DSM) function. However, the underlying molecular and cellular mechanisms by which estrogens control human DSM excitability and contractility are not well known. Here, we used human DSM specimens from open bladder surgeries on 27 patients to elucidate the mechanism by which 17β-estradiol regulates large conductance voltage- a...

The polypeptide patterns of MCF-7 human breast cancer cells (MCF-7gpt) and a stably v-H-ras-transfected subclone (MCF-7ras) have been analyzed following estradiol treatment. Since both estradiol and v-H-ras transfection increase tumorigenicity of MCF-7 cells, this study was designed to ascertain if specific changes in polypeptides were common in both treatments. Separation of cellular and secre...

The present randomized double blind study investigated the effects of a 2 week transdermal estradiol treatment on memory performance in 38 healthy elderly women. Cognitive performance was tested at baseline and after 2 weeks of estradiol or placebo treatment using verbal, semantic, and spatial memory tests as well as a mental rotation task and the Stroop. Initial results showed no differences a...

We used three yeast genetic systems to investigate the estrogen-like activity of octylphenol (OP), bisphenol-A (BPA), o,p'-DDT, and o, p'-DDE to induce human estrogen receptor (hER) dimerization and transcriptional activation. We have demonstrated that OP, BPA, and o, p'-DDT can induce hER ligand-dependent dimerization using a yeast two-hybrid assay. All three xenoestrogens, plus estradiol, enh...

Estrogen replacement therapy in postmenopausal women ameliorates cognitive dysfunction and decreases the risk and/or severity of neurodegenerative conditions such as Alzheimer's disease and stroke. Furthermore, estradiol exerts neuroprotective effects in a variety of in vitro and in vivo models of brain injury. We have previously shown that physiological levels of estradiol attenuate ischemic b...

During the female reproductive cycle, the neuroendocrine action of estradiol switches from negative feedback to positive feedback to initiate the preovulatory GnRH and subsequent LH surges. Estrogen receptor-alpha (ERalpha) is required for both estradiol negative and positive feedback regulation of LH. ERalpha may signal through estrogen response elements (EREs) in DNA and/or via ERE-independen...

Kinetic analysis of the estrogen receptor's cooperative equilibrium [3H]estradiol binding (Sasson, S., and Notides, A. C., (1982) J. Biol. Chem. 257, 11540-11545) provides a sensitive method for probing the binding of partial agonists to the estrogen receptor. We studied the effects of estriol and estrone on the positive cooperativity of [3H]estradiol binding to the partially purified, calf ute...

The involvement of endothelium-derived hyperpolarizing factor (EDHF) in the protective effect of 17beta-estradiol was investigated on the phenylephrine-precontracted carotid artery from cholesterol fed rabbits. Animals were fed for 8 weeks as follows: control group, standard chow; (control+estradiol) group, standard chow+17beta-estradiol; standard chow+1% cholesterol, cholesterol group; or (cho...