Some human breast cancers which contain estrogen receptors (ER) also contain progesterone receptors (PgR), whose presence may indicate that the ER remain responsive to estrogen and can still control specific protein synthesis. To demonstrate a direct role for ER we have used the human breast cancer cell line, MCF-7, which contains ER and low PgR levels. We have studied the effects of addition a...

LH/hCG receptors were disrupted by gene targeting in embryonic stem cells. The disruption resulted in infertility in both sexes. The gonads contained no receptor mRNA or receptor protein. Serum LH levels were greatly elevated, and FSH levels were moderately elevated in both sexes; estradiol and progesterone levels decreased but were not totally suppressed in females; testosterone levels were dr...

background: physical exercise is known to be a stressor stimulus that leads to reproductive disruption.objective: the aim of this study was to evaluate the effect of forced swimming on the uterus and ovaries in mice.materials and methods: adult mice (n=24) were divided into the following threegroups: a, control; b, swimming in water (10popc); and c, swimming in water (23popc).swimmers swam for ...

introduction: lower level of estrogen hormone is considered as an important factor for loss of learning and memory in postmenopausal women. although estrogen replacement therapy is used for compensation, but long-term usage of estrogen is associated with a higher risk of hormonedependent cancers. phytoestrogens, due to fewer side effects, have been proposed to prevent menopause-related cognitiv...

The current study investigated the estrogen agonist-antagonist properties of the selective estrogen receptor modulator, raloxifene (Ral), on neuroprotection and neuronal markers of memory function. Low concentrations of raloxifene significantly reduced basal markers of membrane damage and had no deleterious effect on neuronal survival. However, high concentrations of raloxifene (1000-5000 ng/ml...

Long-term exposure to estradiol is associated with an increased risk of breast cancer, but the mechanisms responsible are not firmly established. The prevailing theory postulates that estrogens increase the rate of cell proliferation by stimulating estrogen receptor (ER)-mediated transcription, thereby increasing the number of errors occurring during DNA replication. An alternative theory sugge...

Estradiol plays a pivotal role in the control of gonadotropin-releasing hormone (GnRH) neuronal function and female reproduction. While positive and negative feedback actions of estradiol that enhance and suppress release of GnRH and LH are primarily mediated through estrogen receptor alpha located in interneurons, a series of recent studies in our laboratory indicate that rapid excitatory acti...

Estradiol, through activation of genomic estrogen receptors, induces changes in synaptic morphology and function in hippocampus, a brain region important for memory acquisition. Specifically, this hormone increases CA1 pyramidal cell dendritic spine density, NMDA receptor (NMDAR)-mediated transmission, and the magnitude of long-term potentiation (LTP) at CA3-CA1 synapses. We recently reported t...

In this report, we demonstrate that NADPH oxidase is activated by tumor necrosis factor-a (TNF-a) plus interferon-g (IFN-g) in human monocytic cells (THP-1 cells) differentiated with phorbol ester (PMA) and that physiological concentration of 17h-estradiol inhibits NADPH oxidase activity in THP-1 cells stimulated with TNF-a plus IFN-g. This effect is mediated by estrogen receptor based on estro...