Hamster: a unique model for studying implantation

仓鼠：研究植入的独特模型

• 批准号: 7341165
• 负责人: Bibhash Chandra Paria
• 金额: $ 25.26万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-01 至 2010-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7341165
• 关键词: Animal Model; Appendix; Aromatase; Aromatase Inhibitors; C19 steroid; Cells; Comparative Study; Cytochrome P450; DTR gene; Defect; Embryo; Embryonic Development; Enzymes; Epidermal Growth Factor; Epithelial; Epithelium; Estrogen Receptor 2; Estrogen Receptor alpha; Estrogen Receptors; Estrogens; Event; Failure; Family suidae; Female infertility; Fertility; Figs - dietary; Gene Expression; Genes; Goals; Grant; Growth Factor; Growth Factor Gene; Hamsters; Heparin Binding; Hormonal; Human; Immunofluorescence Immunologic; Immunohistochemistry; In Situ Hybridization; In Vitro; Infertility; Investigation; Macaca mulatta; Messenger RNA; Modeling; Molecular; Morula; Mus; Oryctolagus cuniculus; Ovarian; Patient currently pregnant; Play; Pre-implantation Embryo Development; Pregnancy; Preparation; Process; Production; Progesterone; Proteins; Rattus; Regulation; Reverse Transcriptase Polymerase Chain Reaction; Role; Source; Staging; Steroids; Study models; Sus scrofa; Testing; Time; Uterus; Western Blotting; Woman; Work; base; blastocyst; cyclooxygenase 2; day; embryo culture; implantation; in vitro Model; in vivo; insight; leukemia inhibitory factor; natural Blastocyst Implantation; paracrine; research study; steroid hormone; uterine receptivity; ward

DESCRIPTION (provided by applicant): Ovarian progesterone is essential for implantation in all species studied. However, the requirement of embryonic estrogen in this process is still an unsettled issue, except in mice and rats in which embryos do not possess the machinery for estrogen synthesis. Implantation can occur in several species including hamsters and perhaps in humans in the absence of ovarian estrogen if progesterone is provided. However, our recent study shows that: (1) estrogen, but not progesterone, regulates the uterine expression of heparin binding EGF-like growth factor gene (Hegfl) in ovariectomized hamsters, and (2) Hegfl expression occurs in the uterine luminal epithelium surrounding the blastocyst at the time of implantation in the absence of circulating estrogen in progesterone-primed hypophysectomized pregnant hamsters. These results suggest that hamster blastocysts could be an alternative source of estrogen that acts locally to induce Hegfl gene expression in the uterus. Indeed, our preliminary experiments suggest the presence of cytochrome P450 aromatase protein in hamster morulae and blastocysts. Furthermore, the exposure of hamster morulae to a steroidal cytochrome P450 aromatase inhibitor in culture significantly inhibits the formation of blastocysts. These observations together with our preliminary results of estrogen receptor-alpha expression in preimplantation hamster embryos and uterus at the time of implantation led us to postulate that this species does not depend on ovarian estrogen, but requires embryonic estrogen to initiate embryonic and uterine changes required for implantation. However, neither the synthesis nor the role of embryonic estrogen in blastocyst formation, uterine receptivity and implantation in hamsters has been resolved. Thus, our specific aims to study in hamsters: (1) Do hamster preimplantation embryos produce estrogen? (2) Is embryonic estrogen required for morula-blastocyst transformation? (3) Is embryonic estrogen required for the establishment of uterine receptivity for implantation? (4) Does systemic estrogen induce uterine receptivity and implantation in the absence of embryonic estrogen? We will use multiple approaches including RT-PCR, in situ hybridization, immunohistochemistry, immunofluorescence, Western blotting, embryo culture and transfer and others to accomplish our goals. With better understanding of the mechanisms of embryo development and uterine receptivity for implantation, issues concerning fertility and infertility in women will be more effectively managed.

描述（由申请人提供）：卵巢黄体酮是所有研究物种着床所必需的。然而，除了小鼠和大鼠的胚胎不具备雌激素合成机制外，胚胎雌激素在这一过程中的需求仍然是一个悬而未决的问题。在没有卵巢雌激素的情况下，如果提供黄体酮，包括仓鼠在内的一些物种可能也会发生着床。然而，我们最近的研究表明：(1)雌激素而不是孕激素调节去卵巢仓鼠子宫中肝素结合egf样生长因子基因（Hegfl）的表达；(2)在孕激素引发的去卵巢仓鼠中，在缺乏循环雌激素的情况下，Hegfl在着床时胚泡周围的子宫腔上皮中表达。这些结果表明，仓鼠囊胚可能是雌激素的另一种来源，可在子宫局部诱导Hegfl基因表达。事实上，我们的初步实验表明，细胞色素P450芳香化酶蛋白存在于仓鼠胚泡和毛囊中。此外，仓鼠桑葚胚暴露于甾体细胞色素P450芳香化酶抑制剂的培养中可显著抑制囊胚的形成。这些观察以及我们在着床前仓鼠胚胎和子宫中雌激素受体α表达的初步结果使我们假设该物种不依赖于卵巢雌激素，但需要胚胎雌激素来启动着床所需的胚胎和子宫变化。然而，胚胎雌激素的合成及其在仓鼠囊胚形成、子宫容受性和着床中的作用尚未得到解决。因此，我们的具体目的是在仓鼠身上进行研究：(1)仓鼠着床前胚胎是否产生雌激素？(2)桑葚胚转化是否需要胚胎雌激素？(3)子宫着床接受性的建立是否需要胚胎雌激素？(4)在没有胚胎雌激素的情况下，全身雌激素是否能诱导子宫容受性和着床？我们将使用多种方法，包括RT-PCR，原位杂交，免疫组织化学，免疫荧光，Western blotting，胚胎培养和转移等来实现我们的目标。随着对胚胎发育和子宫着床接受性机制的深入了解，妇女生育和不孕症问题将得到更有效的解决。