Early Embryonic Heart Function and the Influence of InternalExternal Environmental Factors on Developmental Trajectories

我们对包括哺乳动物在内的任何脊椎动物早期胚胎形成的心血管系统的了解仍然非常有限。简单地说，从“有机体生理学”的角度来看，脊椎动物胚胎仍然是一个“黑盒子”。因此，本提案的主要目标是：1)通过实验确定心脏发育早期导致血流和压力产生的生理机制来研究心血管功能的发生；2)明确界定和描绘心血管发展的“关键窗口期”；3)确定在胚胎发育早期建立并由基因型决定的“发育轨迹”是否可以通过环境因素的挑战而改变，从而产生改变的胚胎/幼虫表型。将对斑马鱼、非洲爪蛙和家禽进行测量。第一阶段的实验将包括在胚胎早期的体内生理变量的测量。第二个实验阶段将包括在低氧条件下饲养发育中的胚胎种群，并评估它们的生理性能和解剖发育。这些关于早期胚胎心血管发育以及相关环境因素（如缺氧）对其影响的研究将在脊椎动物生理学和发育生物学方面具有非常广泛的适用性，特别是在几乎完全缺乏脊椎动物胚胎的类似公开数据的情况下。

9616138 Burggren Our understanding of the forming cardiovascular system of early embryos remains extraordinarily limited for any vertebrate, including mammals. Simply put, the vertebrate embryo remains a "black box" from an "organismal physiology" perspective. Consequently, the major objectives of this proposal are to: 1) investigate the onset of cardiovascular function by determining experimentally the physiological mechanisms leading to flow and pressure generation in early stages of heart development; 2) clearly define and delineate the "critical windows" for cardiovascular development; 3) determine whether "development trajectories" - established early in embryonic development and dictated by genotype - can be diverted through challenge by environmental factors to produce altered embryonic/larval phenotype. Measurements will be made zebrafish, the African clawed frog, and the domestic fowl. The first phase of experiments will include measurements during the early embryonic period of in vivo physiological variables. The second experimental phase will consist of rearing populations of developing embryos under low oxygen and assessing their physiological performance and anatomical development. These studies on early embryonic cardiovascular development and how relevant environmental factors (e.g. hypoxia) impact it will have very broad applicability to both vertebrate physiology and developmental biology, particularly in the almost complete absence of similar published data for vertebrate embryos.