Hamster: A Unique Model for Studying Implantation

描述（由申请人提供）：每个物种都有自己的植入策略。利用跨物种异种芯片技术，我们发现c型利钠肽（CNP）可能是仓鼠的植入信号分子，仓鼠表现出与兔、猪、猴和人类相似的黄体酮依赖性植入。CNP是利钠肽（NP）家族的第三个成员，该家族还包括心房和脑利钠肽（ANP和BNP）。所有NPs都通过两种类型的GC受体（GC - a和GC- b）起作用。CNP更倾向于GC-B，而ANP和BNP更倾向于GC-A。我们的初步结果表明，虽然CNP信号在仓鼠着床部位占主导地位，但ANP/BNP和CNP信号在小鼠和仓鼠着床部位均有活性。这些观察结果，再加上CNP和ANP的子宫松弛特性、BNP的滋养细胞生长、BNP诱导着床以及GC-B阴性女性的不孕，表明NP信号强烈影响着床过程。因此，我们提出了一个工作假设，即NP配体受体信号影响着床的几个生物学和临床重要方面：1)受体子宫的肌张力，2)着床前囊胚-子宫的交叉对话，3)滋养细胞的附着、生长和侵袭，以及4)子宫间质细胞的脱胞。因此，我们的具体目的是在仓鼠身上研究：1)囊胚在着床前和着床时对子宫的影响；2) NPs在着床前和着床期间对子宫收缩力的调节作用；3) NP配体受体信号在着床起始和脱个体化中的作用。我们将使用多种实验方法，包括qPCR， Northern和原位杂交，免疫组织化学，体内腺病毒载体驱动基因抑制，体外子宫收缩研究等来实现我们的目标。破译植入所需的调节事件将有助于深入了解女性植入缺陷和不孕症的潜在原因。因此，这些显示黄体酮依赖性植入的仓鼠研究可能为开发诊断和治疗工具提供有用的信息，这些工具可用于检测、预防和治疗雌性生殖障碍，并改进辅助生殖和避孕技术。

DESCRIPTION (provided by applicant): Each species has developed its own strategy for implantation. Using a cross- species heterologous microarray we identified C-type natriuretic peptide (CNP) as a possible implantation signaling molecule in hamsters which exhibit progesterone- dependent implantation similar to rabbits, pigs, monkeys and most likely in humans. CNP is the third member of the natriuretic peptide (NP) family which also includes atrial- and brain-NPs (ANP and BNP). All NPs act via two types of guanylyl cyclase (GC) receptors, GC-A and GC-B. CNP has more preference for GC-B, while ANP and BNP prefer GC-A. Our preliminary results show that while CNP signaling predominates at the implantation site of hamsters, both ANP/BNP and CNP signalings are active at the implantation sites of both mice and hamsters. These observations together with uterine relaxation properties of CNP and ANP, trophoblast outgrowth by BNP, induction of implantation by BNP, and infertility in GC-B null females suggest that NP signaling strongly influences the implantation process. Thus, we formulated a working hypothesis that NP ligand-receptor signaling influences several biologically and clinically important aspects of implantation: 1) muscular tone of the receptive uterus, 2) blastocyst-uterine cross talk prior to implantation, 3) trophoblast attachment, outgrowth and invasion, and 4) uterine stromal cell decidualization. Therefore, our Specific Aims are to study in hamsters: 1) influence of the blastocyst on the uterus prior to and at the time of implantation; 2) functions of NPs in regulation of uterine contractility prior to and during the time of implantation; and 3) the role of NP ligand-receptor signaling in initiation of implantation and decidualization. We will use multiple experimental approaches including qPCR, Northern and in situ hybridization, immunohistochemistry, in vivo adenoviral vector-driven gene inhibition, in vitro uterine contraction studies, and others to accomplish our goals. Deciphering the regulatory events required for implantation will provide insight into the potential causes of defects in implantation and infertility in women. Thus, these studies in hamsters that show progesterone-dependent implantation may provide useful information in the development of diagnostic and therapeutic tools that can be used in detection, prevention and treatment of female reproductive disorders, and improved technologies for assisted reproduction and contraception. PUBLIC HEALTH RELEVANCE: This proposal will address the role of natriuretic peptide ligand-reeptor signaling in the regulation of early pregnancy events. Defects in the uterus can cause infertility and pregnancy loss in women. This research will provide deeper insight into the molecular mechanisms underlying establishment of uterine receptivity/implantation/decidualization, and help to design clinical therapies to identify, treat and prevent reproductive problems in women.