Mechanisms of Hormonal Regulation of the Sodium Chloride Cotransporter

氯化钠协同转运蛋白的激素调节机制

• 批准号: 8323954
• 负责人: Robert S Hoover
• 金额: $ 29.16万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-25 至 2015-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8323954
• 关键词: Alanine; Aldosterone; Angiotensin II; Animal Experimentation; Antihypertensive Agents; Blood Pressure; Calcium-Sensing Receptors; Cell Culture Techniques; Cell model; Cells; Chloride Ion; Chlorides; Data; Development; Endocytosis; Epidermal Growth Factor; Epidermal Growth Factor Receptor; Generations; Glucocorticoids; Hereditary Disease; Hormonal; Hormones; Hypertension; Immunoblotting; Immunohistochemistry; Investigation; Kidney; Knockout Mice; Knowledge; Lead; Leucine Zippers; Link; Lysine; MAP Kinase Gene; MAPK3 gene; Mammalian Cell; Mediating; Mediator of activation protein; Mitogen Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Molecular; Oxidative Stress; Pathogenesis; Pathway interactions; Pharmaceutical Preparations; Phosphorylation; Phosphotransferases; Physiological; Play; Process; Proline; Proteins; Publishing; Regulation; Risk Factors; Role; Signal Transduction; Site; Sodium; Sodium Chloride; Stimulus; Surface; Transactivation; Transgenic Mice; Transgenic Organisms; Tubular formation; Ubiquitination; Wild Type Mouse; absorption; base; biological adaptation to stress; blood pressure regulation; defined contribution; hormone regulation; human disease; in vivo; insight; mortality; public health relevance; salt balance; sodium-chloride cotransporter; thiazide

DESCRIPTION (provided by applicant): The thiazide-sensitive sodium chloride cotransporter (NCC) is one of the key determinants of salt balance and thus systemic blood pressure. However, in contrast to other important effectors of salt balance we know little about how hormonal and physiological signals alter activity of this cotransporter. Preliminary data demonstrates the role of the ERK1/2 MAPK (Extra-cellular signal-Regulated Kinases 1 and 2 Mitogen-Activated Protein Kinases) pathway in the ubiquitination and endocytosis of NCC. With-No-Lysine Kinase 1 and 4 (WNK1 and WNK4), Ste20-related proline alanine-rich kinase (SPAK) and Oxidative Stress Response-1 (OSR1) are also important regulators of NCC, and there is data that some hormones regulate NCC. However, a link between hormones and the intracellular pathways that mediate the effects of hormones on NCC has not been established. The broad hypothesis of the proposed investigation is that NCC is subject to hormonal regulation that proceeds through modulation of the kinases ERK1/2, SPAK/OSR and WNKs. Aim 1 will define the hormonal regulation of NCC through activation of ERK1/2 MAPK. ERK1/2 MAPK will be examined as a central mediator of the hormonal/physiological effects of Epidermal Growth Factor (EGF) and the Calcium-sensing Receptor (CaSR) on NCC. The mechanism of ERK1/2 activation and the roles of ubiquitination and endocytosis in this process will be thoroughly examined for each hormone, tracing a pathway from hormonal stimulus to functional effect. Aim 2 will determine the hormonal regulation of NCC by Aldosterone through ERK1/2 MAPK and SPAK/OSR and the mechanisms underlying these effects. ERK1/2 inhibition and SPAK/OSR activation by Aldosterone may lead to increased NCC activity. The role of WNKs in these pathways will be thoroughly examined. Aim 3 will determine the underlying molecular mechanisms mediating hormonal regulation of NCC by Angiotensin II. The roles of each of these kinase pathways will be examined with a particular emphasis on WNKs. Mammalian cell culture, isolated tubule microperfusion and whole animal experimentation will be utilized to examine effects at the cellular/molecular, tubular and organismal level. Knowledge of hormonal regulation of blood pressure has played a critical role in the development of new therapies to treat hypertension, the single risk factor that contributes the most to worldwide mortality. These studies will provide vital information on the regulation of this important effector of blood pressure homeostasis. PUBLIC HEALTH RELEVANCE: The sodium chloride cotransporter (NCC) is an important salt absorptive pathway in the mammalian kidney that is the site of action of one of the most effective classes of anti- hypertensive medications and plays a key role in genetic disorders of hypertension. Despite the importance of this cotransporter in human disease, we know little about its hormonal regulation. This investigation of the hormonal regulation of this key effector of blood pressure will provide invaluable insight into the pathogenesis of Hypertension.

描述（由申请人提供）：噻嗪敏感性氯化钠协同转运蛋白（NCC）是盐平衡的关键决定因素之一，因此也是全身血压的关键决定因素。然而，与盐平衡的其他重要效应物相比，我们对激素和生理信号如何改变这种协同转运蛋白的活性知之甚少。初步数据表明ERK 1/2 MAPK（细胞外信号调节激酶1和2丝裂原活化蛋白激酶）途径在NCC的泛素化和内吞作用中的作用。无赖氨酸激酶1和4（WNK 1和WNK 4）、与Ste 20相关的富含脯氨酸丙氨酸的激酶（SPAK）和氧化应激反应-1（OSR 1）也是NCC的重要调节因子，并且有数据表明一些激素调节NCC。然而，激素和介导激素对NCC作用的细胞内途径之间的联系尚未建立。所提出的研究的广泛假设是NCC受到激素调节，其通过激酶ERK 1/2、SPAK/OSR和WNK的调节进行。目的1阐明ERK 1/2 MAPK对NCC的激素调节作用。ERK 1/2 MAPK将作为表皮生长因子（EGF）和钙敏感受体（CaSR）对NCC的激素/生理作用的中心介质进行检查。ERK 1/2激活的机制和泛素化和内吞作用在这个过程中的作用将被彻底检查每种激素，跟踪从激素刺激到功能效应的途径。目的2探讨醛固酮通过ERK 1/2 MAPK和SPAK/OSR对NCC的激素调节作用及其机制。ERK 1/2抑制和SPAK/OSR激活醛固酮可能导致NCC活性增加。WNK在这些途径中的作用将被彻底研究。目的3将确定潜在的分子机制介导的激素调节NCC的血管紧张素II。这些激酶途径中的每一个的作用将被检查，特别强调WNK。将利用哺乳动物细胞培养、分离的小管微灌注和整体动物实验来检查细胞/分子、小管和生物体水平的效应。激素调节血压的知识在开发治疗高血压的新疗法中发挥了关键作用，高血压是导致全球死亡率最高的单一风险因素。这些研究将提供重要的信息调节血压稳态的这一重要效应。 公共卫生相关性：氯化钠协同转运蛋白（NCC）是哺乳动物肾脏中重要的盐吸收途径，是最有效的一类抗高血压药物的作用部位，并且在高血压遗传性疾病中起关键作用。尽管这种协同转运蛋白在人类疾病中很重要，但我们对其激素调节知之甚少。对这种血压关键效应物的激素调节的研究将为高血压的发病机制提供宝贵的见解。