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1.
猪雌激素受体基因研究进展   总被引:2,自引:0,他引:2  
雌激素受体(ESR)是一种核酸受体,具有转录调控蛋白质的功能,影响着雌激素基因在雌性脊椎动物组织的表达,从而对第二性征、繁殖周期、生殖力、妊娠维持等方面产生影响。本文对雌激素受体的分布、生物学作用、分子结构、基因定位、多态性及其与猪繁殖性能的关系等方面作一综述。  相似文献   
2.
AIM To investigate the effects of 17β-estradiol (E2) treatment on the mesenteric lymphatic microcirculation and isolated lymphatic contractility in rats after hemorrhagic shock, and to explore the relationship between contractility and the difference between intra- and extracellular calcium ion concentrations ([Ca2+]) of lymphatic smooth muscle cells (LSMCs). METHODS Male Wistar rats were divided into sham group, shock group and shock+E2 group. The rats were subjected to hemorrhage [(40±2) mmHg for 90 min] and resuscitation with or without subcutaneous injection of E2 (2 mg/kg). After resuscitation for 3 h, the mesenteric lymphatic microcirculation in vivo was observed. Moreover, the isolated mesenteric microlymphatic rings were prepared for the observations of lymphatic contractility evaluated by the indexes including end-systolic diameter, end-diastolic diameter, contraction frequency (CF) and passive diameter. Meanwhile, the difference between intra- and extracellular [Ca2+] of LSMCs was recorded during lymphatic contraction. RESULTS Treatment with E2 significantly enhanced the CF, total contractile fraction and lymphatic dynamics index in vivo in the rats after hemorrhagic shock, and increased the CF, the fractional pump flow and the difference between intra- and extracellular [Ca2+] of LSMCs in isolated lymphatics from the shocked rats (P<0.05). CONCLUSION Estrogen treatment enhances lymphatic contractility in rats after hemorrhagic shock, which is related to enhancement of difference between intra- and extracellular [Ca2+] of LSMCs.  相似文献   
3.
Sex change in coral reef fish   总被引:1,自引:0,他引:1  
Gonadal differentiation can take many forms in fish, ranging from gonochorism, where individuals directly develop as male or female and finally possess only testis or ovaries at sexual maturation, to hermaphroditism where the same individuals can produce mature male and female gametes at some time in their lives. Hermaphrodite fish are, thus, an excellent model for studying the plasticity of sex determination and differentiation in vertebrates. We have shown that sex steroids play a principal role in sex differentiation and sex change in fish. Our laboratory implements several fish models that undergo sex change from female to male or male to female or in both directions. In this review, we will briefly discuss recent advances in our understanding of the mechanism of sex change in coral reef fish.  相似文献   
4.
AIM: To investigate the relationship between the expression of estrogen receptor α36 (ER-α36) and the invasion of gastric cancer cells. METHODS: SGC7901 cells were treated with 17β-estradiol at high or low concentration. The invasion of gastric cancer cells and the expression of ER-α36 were detected. The SGC7901 cells with the characteristics of stable low expression and high expression of ER-α36 were constructed. The invasion ability and microRNA sequences were determined in above-mentioned recombinant cells. RESULTS: The decreased invasion ability and ER-α36 expression were detected in SGC7901 cells treated with low concentration of 17β-estradiol. The situation was the opposite in the cells treated with high concentration of 17β-estradiol. The expression of miR-143 was significantly decreased in the SGC7901 cells with stable high expression of ER-α36 and was increased in the SGC7901 cells with stable low expression of ER-α36. CONCLUSION: The expression of ER-α36 is positively related to the invasion of gastric cancer cells. It is possible that miR-143 plays an important role in the regulation of gastric cancer invasion.  相似文献   
5.
AIM: To investigate the effect of estrogen antagonists on the in vitro growth of human prolactinomas. METHODS: RT-PCR was applied to the detection of estrogen receptor (ER) mRNA expressed in a human prolactinomas CH3 cell strain. Estradiol and 4-hydroxytamoxifen (OHTam) were added respectively at different concentrations into the culture medium. Cell number and levels of ER mRNA were examined. RESULTS: The growth of CH3 cells became slower in estrogen-deprived medium than that in nomal culture and was higher in medium containing estrogen(E2) at concentration of 10-8 mol/L than at concentration of 10-6 mol/L. OHTam (10-6mol/L) inhibited the growth of CH3 cell strain treated with E2. The expression of ER mRNA in CH3 cells was observed, the levels of ER mRNA in the E2 (10-8mol/L) group, higher than those in estrogen deprived group. OHTam (10-6mol/L) obviously inhibited the expression of ER mRNA. CONCLUSION: The growth of CH3 cells depends on estrogen, estrogen antagonists inhibits the growth of CH3 cells and decline the levels of ER mRNA. ER levels in human prolactinomas cell lines can be auto-regulated.  相似文献   
6.
Although the exact mechanism(s) by which estradiol (E2) enhances muscle growth in a number of species, including humans and cattle, is not known, E2 treatment has been shown to stimulate proliferation of cultured bovine satellite cells (BSCs). This is particularly significant because satellite cells are the source of nuclei needed to support postnatal muscle fiber hypertrophy and are thus crucial in determining the rate and extent of muscle growth. The objective of this study was to assess the role of estrogen receptor-α (ESR1) and the type 1 insulin-like growth factor receptor (IGFR1) in E2-stimulated proliferation of cultured BSCs. To accomplish this, we have used small interfering RNA (siRNA) to silence expression of ESR1 or IGFR1 and assessed the effects on E2-stimulated proliferation in BSC cultures. In BSCs treated with nonspecific siRNA, E2 significantly (P < 0.05) stimulates proliferation under conditions in which neither IGF-1 nor IGF-2 expression is increased; however, treatment of ESR1- or IGFR1-silenced cells with E2 does not significantly stimulate proliferation. These results indicate that both ESR1 and IGFR1 are required for E2 to stimulate proliferation in BSC cultures. The fact that this occurs under culture conditions in which neither IGF-1 nor IGF-2 mRNA expression is increased strongly suggests that E2 activates IGFR1 via a mechanism that does not involve increased IGF-1 or IGF-2 binding to the receptor.  相似文献   
7.
8.
Maternal recognition of pregnancy refers to the requirement for the conceptus(embryo and its associated extraembryonic membranes) to produce a hormone that acts on the uterus and/or corpus luteum(CL) to ensure maintenance of a functional CL for production of progesterone;the hormone required for pregnancy in most mammals.The pregnancy recognition signal in primates is chorionic gonadotrophin which acts directly on the CL via luteinizing hormone receptors to ensure maintenance of functional CL during pregnancy.In ruminants,interferon tau(IFNT) is the pregnancy recognition signal.IFNT is secreted during the peri-implantation period of pregnancy and acts on uterine epithelia to silence expression of estrogen receptor alpha and oxytocin receptor which abrogates the oxytocin-dependent release of luteolytic pulses of prostaglandin F2-alpha(PGF) by uterine epithelia;therefore,the CL continues to produce progesterone required for pregnancy.Pig conceptuses secrete interferon delta and interferon gamma during the peri-implantation period of pregnancy,but there is no evidence that they are involved in pregnancy recognition signaling.Rather,pig conceptuses secrete abundant amounts of estrogens between Days 11 to 15 of pregnancy required for maternal recognition of pregnancy.Estrogen,likely in concert with prolactin,prevents secretion of PGF into the uterine venous drainage(endocrine secretion),but maintains secretion of PGF into the uterine lumen(exocrine secretion) where it is metabolized to a form that is not luteolytic.Since PGF is sequestered within the uterine lumen and unavailable to induce luteolysis,functional CL are maintained for production of progesterone.In addition to effects of chorionic gonadotrophin,IFNT and estrogens to signal pregnancy recognition,these hormones act on uterine epithelia to enhance expression of genes critical for growth and development of the conceptus.  相似文献   
9.
Estrogen has many biological activities and extensive clinical applications. Hemorrhagic shock-induced major organ dysfunction and injury, which are related to sex differences, play a triggering role in irreversible shock. The present article reviews the role of estrogen in alleviating hemorrhagic shock-induced organ injury by analyzing and summarizing the recent studies, thus expanding the clinical application of estrogen and providing a novel approach for treatment of severe hemorrhagic shock.  相似文献   
10.
综述了催产素(OT)、精氨酸加压素(AVP)、性激素(包括雌激素、孕酮、雄性激素)这些神经激素与啮齿类动物的社会识别关系的研究进展。  相似文献   
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