The human estrogen receptor-alpha, a member of the nuclear receptor superfamily, is a ligand-regulated transcriptional modulator. Because comparatively little is known about the extreme carboxyl-terminal region of the estrogen receptor (F domain), we used secondary structure prediction to design mutations that delete the F domain (S554stop), disrupt a possible turn (G556L/G557L), and alter a pr...

Estrogen receptor and its ligand, estradiol, have long been thought to be essential for survival, fertility, and female sexual differentiation and development. Consistent with this proposed crucial role, no human estrogen receptor gene mutations are known, unlike the androgen receptor, where many loss of function mutations have been found. We have generated mutant mice lacking responsiveness to...

Mice, rats, and humans have two types of estrogen receptors, estrogen receptor-alpha (ERalpha) and estrogen receptor-beta (ERbeta). Estrogen receptor-alpha gene-disrupted (ERalpha-disrupted) mice bear two nonfunctional copies of the ERalpha gene. This mutation blocks the synthesis of full-length ERalpha, renders the animals infertile, and inhibits the induction of female sexual behaviors by est...

In order to accurately determine sex hormone dependency and hormone responsiveness in human esophageal carcinoma, the effects of sex hormones on the growth of esophageal carcinoma cell lines, KSE-1 and KSE-2 cells, were examined in vitro and in vivo. Cell proliferation of cultured KSE-1 cells was inhibited by treatment of estradiol and enhanced by dihydrotestosterone (DHT), whereas KSE-2 cells ...

The significance of in vitro aromatization of [7 alpha-3H]testosterone to estradiol by human breast cancer has been investigated by correlation with (a) estrogen receptor activity and (b) clinical response to endocrine therapy. Evidence for estradiol synthesis was obtained in 66 and estrogen receptor activity in 81 of 110 tumors. Whereas most estrogen receptor-positive tumors synthesized estrad...

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exerts its toxic action via the aryl hydrocarbon (Ah) receptor, which induces a battery of xenobiotic-metabolizing enzymes, including the cytochrome P450 isozyme, CYP1A1. TCDD-induced 7-ethoxycoumarin-O-deethylase activity was reduced 75% in cultured human endometrial ECC-1 cells exposed to various concentrations of 17beta-estradiol for up to 72 h, wit...

Background: Estradiol and progesterone as well as hippocampal GABAA receptors are believed to play a role in the modulation of pain. The aim of present study was to investigate the effect of intrahippocampal injections of GABAA receptor agonist (muscimol) and GABAA receptor antagonist (picrotoxin) on pain sensitivity during estrous cycle. Methods: Pain sensitivity was evaluated in rats ...

Plasma leptin concentrations increase as growing dairy heifers approach puberty and have greater plasma estrogen. In intact and ovariectomized rodents, estrogen has been shown to modulate expression of leptin and its receptor (Ob-R). To determine if estrogen regulates the bovine leptin system, prepubertal dairy heifers were ovariectomized at 140 d of age or left intact. A month later, both grou...

The effects of 17h-estradiol on the a,h-me ATP-induced currents were studied on dorsal root ganglion (DRG) neurons using whole-cell recording technique. Three types of currents (transient, sustained or biphasic) were evoked by a,h-me ATP in acutely dissociated DRG neurons. When neurons were pre-incubated with 17h-estradiol (10–1000 nM) for 4 min, an inhibition of the transient current and the t...