Background: Use of hormone replacement therapy (HRT) may increase the risk of adult-onset asthma in women. Various in vitro studies have reported that estradiol stimulates human mast cell lines causing release of allergic mediators which was not observed in estrogen receptor-alpha (ER-alpha) knockout mice. Thus, estrogen might be a key element in occurrence of asthma. In the present study, we p...

the cyclical changes in the gonadotropins stimulate ovarian follicular development either to the ovulatory stage or to undergo atresia. one such intrafollicular factor may be inter-cellular communication via gap junctions. we have examined the effects of two agents (retinoids and alkanols), known to disrupt or uncouple gap junction, on fsh-stimulated lh receptor induction and progestrone synthe...

The present study shows that melatonin prevents, within the first cell cycle, the estradiol-induced growth of synchronized MCF7 breast cancer cells. By using nuclear extracts of these cells, we first examined the binding of estradiol-estrogen receptor complexes to estrogen-responsive elements and found that the addition of estradiol to whole cells activates the binding of the estrogen receptor ...

Introduction: Neurohormones like testosterone and estradiol have an important role in learning and memory. The hippocampus is essentially involved in learning and memory, and is known to be a target for estradiol actions. Estrogen receptors (ERs) are highly expressed in CA1 of rat hippocampus, and mediate the effects of estrogen on learning and memory. Estradiol receptor belong to a family ...

Avian vitellogenin-cauliflower mosaic virus hybrid gene is effectively transcribed in vitro in the homologous embryonic liver nuclei system. The transcription of the hybrid gene is modulated by the addition of an estradiol-receptor preparation that has been shown to bind selectively to an upstream region of cloned vitellogenin gene. Stimulation of the transcription of cloned vitellogenin hybrid...

Introduction: Beside its autonomic functions, the nucleus paragigantocellularis lateralis (LPGi) is involved in the descending pain modulation. 17β-Estradiol is a neuroactive steroid found in several brain areas such as LPGi. Intra-LPGi microinjection of 17β-estradiol can elicit the analgesic responses. 17β-Estradiol modulates nociception by binding to estrogenic receptors as wel...

The role of antioxidants in prevention and treatment of cancers have been reported by several studies. In our investigation we studied the effects of ascorbic acid, ?-tocopherol, and sodium selenite on proliferation of two breast cancer cell lines: T47D (estrogen-receptor positive) and MDA-MB-231 (estrogen-receptor negative). We also used 17-?-estradiol as positive control for proliferation of ...

In the adult female rat, the densities of dendritic spines and synapses on hippocampal CA1 pyramidal cells are dependent upon the ovarian steroid estradiol; moreover, spine and synapse density fluctuate naturally as ovarian steroid levels vary across the estrous cycle. To determine whether the effects of estradiol on dendritic spine density require activation of specific neurotransmitter system...