LONGITUDINAL STUDY OF VOLUME EXPANSION IN HEALTHY PREGNANT WOMEN

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。慢性高血压由不同的机制维持，包括：(1)动脉充盈过度(容量依赖性高血压)；(2)动脉收缩而不增加容量(血管收缩高血压)；或(3)两者的组合。尽管肾脏灌流压力增加，但肾脏通过维持超过血管容量的钠和容量发挥关键作用。据估计，30%-40%的患者患有容量依赖型高血压。在正常情况下，体积扩张和甲状旁腺激素(PTH)导致肾脏近曲小管对钠和磷的吸收减少。严重的是，这种对钠和磷的排斥可能是由于近端小管刷状边界蛋白的磷酸化(与钠/磷共同转运体有关)。在容量扩张性高血压的动物模型中，该蛋白的磷酸化在慢性高血压中下调。相比之下，在血管紧缩性高血压的动物模型中，这种蛋白的磷酸化保持不变。正常妊娠是一种体积扩张的状态。出于这个原因，这项研究旨在纵向评估健康孕妇最近发现的一种被认为是调节体积的近端肾小管刷状边界蛋白。孕妇提供了一个机会来研究在正常生理状态下体积变化时调节蛋白的数量和磷酸化的变化。这些信息将有助于理解某些形式的高血压中的调节蛋白。

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. Chronic hypertension is maintained by different mechanisms including: (1) arterial overfilling (volume-dependent hypertension); (2) arterial constriction without increased volume (vasoconstrictive hypertension) ; or (3) a combination of both. The kidneys play a key role by sustaining sodium and volume in excess of vascular capacity despite increases in renal perfusion pressure. It is estimated that 30-40% of patients have a volume-dependent form of hypertension. Under normal conditions, volume expansion as well as parathyroid hormone (PTH) cause decreased resorption of sodium and phosphate in the proximal convoluted tubule of the kidney. Acutely, this rejection of sodium and phosphate may be due to phosphorylation of a proximal tubule brush border protein (related to the sodium/phosphorus co-transporter). In animal models of volume expansion hypertension, the phosphorylation of this protein is down-regulated in chronic hypertension. Contrastingly, in animal models of vasoconstrictive hypertension, the phosphorylation of this protein is maintained. Normal pregnancy is a state of volume expansion. For this reason, this study will aim to evaluate longitudinally in healthy pregnant women a recently characterized proximal renal tubular brush border protein thought to regulate volume. Pregnant women provide an opportunity to study changes in quantity and phosphorylation of the regulatory protein in a normal physiologic state of changing volume. This information will aid in understanding the regulator protein in some forms of hypertension.