Hamster: A Unique Model for Studying Implantation

描述（由申请方提供）：每个物种都制定了自己的植入策略。使用跨物种异源微阵列，我们鉴定了C型利钠肽（CNP）作为仓鼠中可能的植入信号传导分子，所述仓鼠表现出与兔、猪、猴以及最可能在人类中相似的孕酮依赖性植入。CNP是利钠肽（NP）家族的第三个成员，该家族还包括心房和脑NP（ANP和BNP）。所有NP通过两种类型的鸟苷酸环化酶（GC）受体GC-A和GC-B起作用。CNP更偏好GC-B，而ANP和BNP更偏好GC-A。我们的初步结果表明，虽然CNP信号在仓鼠的植入部位占主导地位，但ANP/BNP和CNP信号在小鼠和仓鼠的植入部位都是活跃的。这些观察结果连同CNP和ANP的子宫舒张特性、BNP的滋养层生长、BNP的着床诱导以及GC-B缺失女性的不孕表明NP信号传导强烈影响着床过程。因此，我们提出了一个工作假设，即NP配体-受体信号传导影响着床的几个生物学和临床重要方面：1）接受性子宫的肌张力，2）着床前胚泡-子宫串扰，3）滋养层附着，生长和侵袭，以及4）子宫基质细胞蜕膜化。因此，我们的具体目的是在仓鼠中研究：1）着床前和着床时囊胚对子宫的影响; 2）着床前和着床期间NP在调节子宫收缩力中的功能; 3）NP配体-受体信号传导在着床和蜕膜化启动中的作用。我们将使用多种实验方法，包括qPCR、北方和原位杂交、免疫组织化学、体内腺病毒载体驱动的基因抑制、体外子宫收缩研究等来实现我们的目标。 解读植入所需的调节事件将提供对植入缺陷和女性不孕症的潜在原因的深入了解。因此，在仓鼠中进行的这些研究表明，孕酮依赖性着床可能为开发可用于检测、预防和治疗女性生殖疾病的诊断和治疗工具以及改进辅助生殖和避孕技术提供有用的信息。 公共卫生相关性：本提案将阐述利钠肽配体-受体信号在早孕事件调节中的作用。子宫缺陷会导致女性不孕和流产。这项研究将为建立子宫容受性/着床/蜕膜化的分子机制提供更深入的见解，并有助于设计临床治疗方法来识别，治疗和预防女性生殖问题。

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.