ENDOCRINE REGULATORS OF NORMAL PHOSPHATE HOMEOSTASIS

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。所列机构为中心机构，不一定为研究者机构。磷在涉及中间代谢和能量转移机制的骨骼和细胞功能中起着关键作用。磷、离子钙、甲状旁腺素和骨化三醇表现出日变化。矿物质及其激素调节剂（如磷和1，25（OH）2D）的时间相互关系的研究为我们了解矿物质离子稳态的主要调节剂提供了基础。磷酸盐稳态的遗传和获得性疾病的分子缺陷指向一个共同的，新的，磷酸盐调节途径，涉及一个新发现的成纤维细胞生长因子（FGF-23）。研究人员假设FGF-23在正常生理学中对磷酸盐稳态的调节很重要。这些研究的目的是确定FGF-23全天的变化及其与钙和磷中观察到的每日变化以及与已知的矿物离子稳态、PTH和1，25（OH）2D的激素调节剂的关系。

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.