DISSERTATION RESEARCH: Endocrine Mechanisms and Evolution of the Placenta

论文研究：内分泌机制和胎盘的进化

• 批准号: 9902098
• 负责人: Michael Moore
• 金额: $ 1万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-01 至 2001-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9902098&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Endocrine; Mechanisms; Evolution

During the evolutionary transition from egg-laying to live-bearing, several physical and physiological changes must occur to support the developing embryo. The placenta provides an interface between the mother and fetus, allowing life-sustaining transport of oxygen, nutrients, and wastes. Because the structure of the placenta also permits exchange of steroid hormones, species with relatively recently evolved placentation may face the additional challenge of regulating maternal and fetal hormone levels. Steroid hormones influence pregnancy maintenance and fetal development, so placental effects on these processes could have critical consequences. Study of the evolution of placental physiology in mammals has been limited, because the placenta of eutherian mammals has only one evolutionary origin. However, in reptiles, the placenta has evolved recently and independently as many as 100 times, making this an ideal group for comparative evolutionary study. This proposal aims to define hormonal mechanisms that accompany the evolution of the placenta, and their effects on fetal and maternal hormone levels. The PIs recent work demonstrated that, by reducing the levels of some hormones, the placenta of the mountain spiny lizard may contribute to the isolation of the maternal and fetal hormonal environments. A series of three additional studies will identify placental steroid products, examine interactions between the placenta and fetal glands, and determine the placenta's role in mediation of maternal effects on fetal hormone levels. This comparative mechanistic approach promises to provide novel perspectives on the evolution of placental hormone function.

在从产卵到活产的进化过渡过程中，必须发生一些物理和生理变化来支持发育中的胚胎。胎盘在母亲和胎儿之间提供了一个界面，允许氧气，营养物质和废物的维持生命的运输。由于胎盘的结构也允许类固醇激素的交换，具有相对较新进化的胎盘的物种可能面临调节母体和胎儿激素水平的额外挑战。类固醇激素影响妊娠维持和胎儿发育，因此胎盘对这些过程的影响可能会产生严重后果。由于真兽目哺乳动物的胎盘只有一个进化起源，因此对哺乳动物胎盘生理进化的研究一直受到限制。然而，在爬行动物中，胎盘最近独立进化了多达100次，使其成为比较进化研究的理想群体。该提案旨在定义伴随胎盘进化的激素机制，以及它们对胎儿和母体激素水平的影响。PI最近的工作表明，通过降低某些激素的水平，山棘蜥蜴的胎盘可能有助于隔离母体和胎儿的激素环境。一系列的三个额外的研究将确定胎盘类固醇产品，检查胎盘和胎儿腺体之间的相互作用，并确定胎盘在调解母体对胎儿激素水平的影响中的作用。这种比较机制的方法有望为胎盘激素功能的进化提供新的视角。