共查询到20条相似文献，搜索用时 46 毫秒
1.
Estrogen memory effect in human hepatocytes during repeated cell division without hormone 总被引：3，自引：0，他引：3
Transient stimulation of target tissues by sex steroids can cause long-lasting changes that may facilitate or alter responses to subsequent hormonal treatment. How these altered characteristics are propagated during cell division in the absence of the stimulating hormone is unknown. The human hepatocarcinoma cell line HepG2 was used as a model to examine the effects of estrogen on the synthesis of serum apolipoproteins in vitro. Treatment with low concentrations of estrogen for 24 to 48 hours resulted in long-lasting alterations in the kinetics with which the cells responded to subsequent stimulation with estrogen. Manifestation of this memory effect was correlated quantitatively with the induction and propagation of a moderate-affinity, nuclear, estrogen-binding protein with the characteristics of a type II estrogen receptor. The data indicate that transient exposure of these cells to estrogen can induce changes in their response characteristics and composition of nuclear proteins that are inherited by daughter cells grown in the absence of hormone for more than ten generations. 相似文献
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Neuroendocrine response to estrogen and sexual orientation 总被引：5，自引：0，他引：5
A neuroendocrine component, the positive estrogen feedback effect, thought to be related to sexual orientation and, indirectly, to sexual differentiation, was evaluated in healthy, noninstitutionalized research volunteers. Men and women with a lifelong heterosexual orientation and men with a lifelong homosexual orientation were administered an estrogen preparation known to enhance the concentration of luteinizing hormone in women but not in men. The secretory pattern of luteinizing hormone in the homosexuals in response to estrogen was intermediate between that of the heterosexual men and that of the women. Furthermore, testosterone was depressed for a significantly longer period in the homosexual men than in the heterosexual men. These findings suggest that biological markers for sexual orientation may exist. 相似文献
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An estrogen-binding protein and endogenous ligand in Saccharomyces cerevisiae: possible hormone receptor system 总被引：10，自引：0，他引：10
A protein macromolecule in the cytosol of the unicellular eukaryotic yeast Saccharomyces cerevisiae selectively binds the vertebrate estrogen hormone 17 beta-estradiol with high affinity. Lipid extracts of the yeast cells or the conditioned growth medium yield a substance that can bind competitively to the tritiated estradiol-binding sites in the yeast and to mammalian estrogen receptors. These findings suggest that the binding protein may be a primitive hormone receptor and that the lipid-extractable substance represents the endogenous ligand. 相似文献
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Nuclear estrogen receptor from MCF-7 cells undergoes a time-dependent, hormone-inducible transformation to a form that is less extractable from nuclei and less exchangeable with ligand. This receptor-modifying, intranuclear event is independent of receptor loss (processing) and appears associated with hormone responsiveness (progesterone-receptor induction) in these cells. The magnitude of receptor loss, however, is variable and apparently not a prerequisite for hormone action to induce progesterone receptor. 相似文献
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Ovariectomized female rats treated with estrogen, in dosages too low to provoke mating, displayed this behavior when given subcutaneous injections of synthetic luteinizing hormone-releasing factor (LRF) 48 hours later. Two hours after the injection of LRF, components of female sexual behavior appeared. The lordosis reflex followed mounting by the male, and darting and hopping behavior was quite prevalent. On the other hand, treatment with estrogen followed by luteinizing hormone, follicle-stimulating hormone, or thyrotropin-releasing factor did not induce copulatory behavior. The results suggest that LRF may play a role in induction of mating behavior. 相似文献
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R Hilf 《Science (New York, N.Y.)》1967,155(764):826-827
The milk-like accumulation in the R3230AC mammary adenocarcinoma that follows treatment with estrogen contains lactose, fatty acids, and proteins with electrophoretic properties similar to those of casein and whey of rat milk. This mammary tumor retains the biochemical capacity of the mammary gland in its lactational response to administration of hormone. 相似文献
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Sequence and expression of human estrogen receptor complementary DNA 总被引：95，自引：0，他引：95
G L Greene P Gilna M Waterfield A Baker Y Hort J Shine 《Science (New York, N.Y.)》1986,231(4742):1150-1154
The mechanism by which the estrogen receptor and other steroid hormone receptors regulate gene expression in eukaryotic cells is not well understood. In this study, a complementary DNA clone containing the entire translated portion of the messenger RNA for the estrogen receptor from MCF-7 human breast cancer cells was sequenced and then expressed in Chinese hamster ovary (CHO-K1) cells to give a functional protein. An open reading frame of 1785 nucleotides in the complementary DNA corresponded to a polypeptide of 595 amino acids and a molecular weight of 66,200, which is in good agreement with published molecular weight values of 65,000 to 70,000 for the estrogen receptor. Homogenates of transformed Chinese hamster ovary cells containing a protein that bound [3H]estradiol and sedimented as a 4S complex in salt-containing sucrose gradients and as an 8 to 9S complex in the absence of salt. Interaction of this receptor-[3H]estradiol complex with a monoclonal antibody that is specific for primate ER confirms the identity of the expressed complementary DNA as human estrogen receptor. Amino acid sequence comparisons revealed significant regional homology among the human estrogen receptor, the human glucocorticoid receptor, and the putative v-erbA oncogene product. This suggests that steroid receptor genes and the avian erythroblastosis viral oncogene are derived from a common primordial gene. The homologous region, which is rich in cysteine, lysine, and arginine, may represent the DNA-binding domain of these proteins. 相似文献
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猪FSHβ亚基和ESR基因的研究进展 总被引：6，自引：0，他引：6
在猪的高繁殖力特性研究中，证实促卵泡素（FSH）β亚基和雌激素受体（ESR）基因，是可影响产仔数1－1．5头的主基因，本文从FSHβ亚基和ESR基因的生物作用、基因结构特点及与产仔数的关系等方面作一综述。 相似文献
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Interactions between the gonadal steroids and the immune system 总被引：36，自引：0，他引：36
C J Grossman 《Science (New York, N.Y.)》1985,227(4684):257-261
The immune system is regulated by the gonadal steroids estrogen, androgen, and progesterone, but the circulating levels of these steroids can also be affected by immune system function. Such interactions appear to be mediated through the hypothalamic-pituitary-gonadal-thymic axis and depend on pituitary luteinizing hormone released by thymic factors under the control of the gonadal steroids. 相似文献
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以长白母猪为对照,分析了1月龄、发情期和间情期姜曲海母猪子宫细胞质雌二醇受体(CER)和细胞核雌二醇受体(NER)以及细胞质孕酮受体(CPR)和细胞核孕酮受体(NPR)。3个时期该猪子宫CER分别为351、410和367fmol/mgDNA,其Kd值分别为7.1、4.8和4.0nmol;子宫NER分别为245,1390和620fmol/mgDNA,Kd值为3.7、6.6和4.4nmol;CPR分别为251、364和147fmol/mgDNA;NPR分别为232、337和184fmol/mgDNA。在发情期和间情期,姜曲海母猪子宫NER以及与细胞质受体的比值均比长白母猪高,说明此时姜曲海母猪子宫对雌二醇具有较高的敏感性。性成熟后,试验猪的雌二醇受体和孕酮受体均受它们配体激素的调节。 相似文献
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Receptors for sex and adrenal steroid hormones are absent from fully sequenced invertebrate genomes and have not been recovered from other invertebrates. Here we report the isolation of an estrogen receptor ortholog from the mollusk Aplysia californica and the reconstruction, synthesis, and experimental characterization of functional domains of the ancestral protein from which all extant steroid receptors (SRs) evolved. Our findings indicate that SRs are extremely ancient and widespread, having diversified from a primordial gene before the origin of bilaterally symmetric animals, and that this ancient receptor had estrogen receptor-like functionality. This gene was lost in the lineage leading to arthropods and nematodes and became independent of hormone regulation in the Aplysia lineage. 相似文献
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The Effect ofAdministration of Rutin on Plasma Levels of Estrogen,Prolactin, Growth Hormone and Gene Expression of Their Receptors in Mammary Glands in Ovariectomized Rats 
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下载免费PDF全文 GUO Xu-dong DIAO Qi-yu WANG Yue-ying TU Yan DENG Kai-dong WANG Xin-jian FU Tong YAN Gui-long 《农业科学学报》2012,12(10):1700-1706
The development of mammary glands, endocrine hormone concentrations and the gene expression of related receptors were measured in ovariectomized virgin rats after adminstration of an estrogen-like plant extract, rutin. Thirty-two ovariectomized virgin Wistar rats were randomly assigned to 4 treatments with 8 animals each: gastric infusion of 2 mL normal saline per unovariectomized rat per day (Sham), gastric infusion of 2 mL normal saline per ovariectomized rat per day (Ova), gastric infusion of 60 mg rutin kg-1 body weight (BW) per ovariectomized rat per day (Ova+Rut), or intramuscular injection of 60 μg estradiol kg-1 BW per ovariectomized rat weekly (Ova+Est). Samples of blood and mammary glands were harvested to determine the levels of estrogen (E2), prolactin (PRL) and growth hormone (GH), and the gene expression of estrogen receptors (ER), prolactin receptors (PRLR) and growth hormone receptors (GHR) with radioimmunoassy (RIA) and RT-PCR technology, respectively. The E2 concentration in plasma and gland tissues from the rats of Ovx+Rut or Ovx+Est was higher than that of Ovx (P<0.05), but the plasma E2 concentration from the rats of Ovx+Rut was lower than that of Sham (P<0.05). The order of the PRL concentration in plasma and gland tissues was Ovx 相似文献
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Farooqi IS Bullmore E Keogh J Gillard J O'Rahilly S Fletcher PC 《Science (New York, N.Y.)》2007,317(5843):1355
Studies of the fat-derived hormone leptin have provided key insights into the molecular and neural components of feeding behavior and body weight regulation. An important challenge lies in understanding how the rewarding properties of food interact with, and can override, physiological satiety signals and promote overeating. We used functional magnetic resonance imaging to measure brain responses in two human patients with congenital leptin deficiency who were shown images of food before and after 7 days of leptin replacement therapy. Leptin was found to modulate neural activation in key striatal regions, suggesting that the hormone acts on neural circuits governing food intake to diminish the perception of food reward while enhancing the response to satiety signals generated during food consumption. 相似文献
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雌激素替代加局部疗法治疗老年性阴道炎的疗效观察 总被引：1，自引：0，他引：1
观察雌激素替代加局部疗法治疗绝经后老年性阴道炎的疗效。方法；绝经后老年性阴道炎１２５例随机分为两组；双重作用疗法组５４例，单纯局部疗法组７１例。结果；双重作用疗法组的治愈经为９４．５％，单纯局部疗法组为８８．７％，两组比较差异无显著性，但复发率单纯局部疗法组高达４３．５％，而双重作用疗法组仅为８．６％； 相似文献
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Grebe M 《Science (New York, N.Y.)》2005,310(5745):60-61
In his Perspective, Grebe discusses how a plant proton pump residing in intracellular compartments, rather than in the plasma membrane of the cell surface, regulates growth and development. The pump modulates the expression at the plasma membrane of both a transporter for the hormone auxin and another proton pump. These findings open new views on how plants regulate cell wall acidity and hormone transport during development. 相似文献
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The somatic loss of heterozygosity for normal alleles occurring in human tumors has suggested the presence of recessive oncogenes. The results presented here demonstrate a loss of heterozygosity of several genes on chromosome 11 in primary breast tumors. Restriction fragment length polymorphism analysis of these DNAs further suggests that the most frequent loss of sequences in breast tumors occurs between the beta-globin and parathyroid hormone loci on the short arm of chromosome 11. The loss of heterozygosity for chromosome 11 loci has a significant association with tumors that lack estrogen and progesterone receptors, grade III tumors, and distal metastasis. 相似文献