ENDOCRINE REGULATORS OF NORMAL PHOSPHATE HOMEOSTASIS

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。磷在骨骼和细胞功能中起着关键作用，涉及中间代谢和能量传递机制。磷、离子钙、甲状旁腺素和骨化三醇表现出日变化。对矿物质与其激素调节剂如磷和1，25(OH)2D的时间相互关系的研究为我们理解矿物质离子动态平衡的主要调节剂提供了基础。遗传性和获得性磷酸盐稳态紊乱的分子缺陷指向一种常见的、新的磷酸盐调节途径，涉及一种新发现的成纤维细胞生长因子(FGF-23)。研究人员假设，在正常生理学中，成纤维细胞生长因子-23在调节磷酸盐稳态方面起着重要作用。这些研究的目的是确定成纤维细胞生长因子-23在一天中的变化及其与钙和磷的每日变化的关系，以及已知的矿物质离子稳态激素调节剂PTH和1，25(OH)2D的关系。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Phosphorus plays a critical role in skeletal and cellular functions involving intermediary metabolism and energy-transfer mechanisms. Phosphorus, ionized calcium, PTH and calcitriol exhibit diurnal variation. The study of the temporal interrelationships of the minerals and their hormonal modulators such as phosphorus and 1,25(OH)2D has provided the basis for our understanding of the major modulators of mineral ion homeostasis. Molecular defects in genetic and acquired disorders of phosphate homeostasis point to a common, novel, phosphate-regulatory pathway involving a newly identified fibroblast growth factor (FGF-23). The investigators hypothesize that FGF-23 is important in regulation of phosphate homeostasis in normal physiology. The objective of these studies is to determine the variation of FGF-23 throughout the day and its relationship to daily variation observed in calcium and phosphorus as well as to the known hormonal regulators of mineral ion homeostasis, PTH, and 1,25(OH)2D.