ROLES OF THE PROXIMAL TUBULE RENIN ANGIOTENSIN SYSTEM

近端小管肾素血管紧张素系统的作用

• 批准号: 6183726
• 负责人: JULIE R. INGELFINGER
• 金额: $ 29.52万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-05-01 至 2002-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6183726
• 关键词: angiotensin II; angiotensin receptor; autocrine; cell growth regulation; cell line; glucose transport; hormone receptor; hormone regulation /control mechanism; immunoelectron microscopy; immunologic assay /test; intracellular transport; ion transport; laboratory rat; membrane transport proteins; renal tubular transport; renal tubule; renin angiotensin system

DESCRIPTION: (Adapted from the Applicant's Abstract) Many questions still remain concerning both proximal tubule (PT) renin angiotensin system (RAS) intracellular configuration and mechanisms of its effects. This application uses two lines of immortalized rat PT cells (IRPTC) developed in this application's first cycle to define PT RAS paracrine, autocrine and intracrine effects. It is hypothesized that Ang II and other angiotensins produced locally within PT influence salt and water reabsorption by modulating transporters via specific intracellular signaling mechanisms and intranuclear mechanisms as yet incompletely deduced. Ang II appears to reduce cAMP and stimulate Ca2+ exchanger activity; to increase intracellular calcium via PKC and stimulate Na+/Ca++ transport; and to increase phospholipase A2, stimulating hydrolysis of phosphatidylcholine to lysophosphatidylcholine and fatty acid, influencing sodium transport. Such Ang II effects may be carried out both via surface and intracellular receptors in PT, as suggested by recent evidence from the applicant's laboratory that IRPTC have nuclear Ang II receptors. Specific Aims are to define: I: Intracellular configuration and spatial arrangement of RAS in IRPTC. While all RAS components are clearly demonstrated in PT (and in both lines of IRPTC), actual intracellular localization is incompletely known. Intracellular production, localization and trafficking of RAS components will be defined by immunoelectron microscopy, confocal microscopy, subcellular fractionation plus molecular and cellular techniques. II: Mechanisms of Ang II effect on solute transport in PT. Ang II exhibits a biphasic influence on water and salt transport. The influence of Ang II on transporter regulation will be defined, using Na+/H+ exchanger as a prototype in parallel studies encompassing both molecular biology and cell physiology. Ang II-responsive elements will be sought; effects of Ang II on mRNA and protein regulation of NHEs will be delineated [e.g., mRNA steady state level, stability and localization; immunostaining intensity and pattern [e.g., with trafficking and immunoassay]; and cell signaling and physiology will be defined. III: Ang II and its autocrine and intracrine effects, as these affect PT functions such as growth and repair, and protein processing, hypothesizing that Ang II modulates cell growth and repair. The functional role of Ang II in IRPTCs will be defined by blocking or stimulating RAS components to dissect autocrine effects. IRPTCs have intracellular Ang II receptors; thus, possible intracellular processing of angiotensinogen (renin substrate) will be studied.

描述：（改编自申请人的摘要）许多问题仍然存在 仍然涉及近端小管（PT）的肾素血管紧张素系统（RAS） 细胞内构型及其作用机制。 本申请 使用两种永生化大鼠PT细胞（IRPTC）， 应用程序的第一个周期，以定义PT RAS旁分泌，自分泌和 内分泌效应 假设血管紧张素II和其他血管紧张素 在PT内局部产生的影响盐和水的重吸收， 通过特定的细胞内信号传导机制调节转运蛋白， 核内机制尚未完全推断。 Ang II似乎 降低cAMP和刺激Ca 2+交换器活性;增加细胞内 钙通过PKC并刺激Na +/Ca ++转运;并增加 磷脂酶A2，刺激磷脂酰胆碱水解， 溶血磷脂酰胆碱和脂肪酸，影响钠转运。 等 血管紧张素Ⅱ的作用可能通过细胞表面和细胞内两种途径进行， PT中的受体，如来自申请人的最新证据所表明的， IRPTC细胞核内有血管紧张素Ⅱ受体。 具体的目标是 定义：I：细胞内RAS的构型和空间排列， IRPTC。 虽然所有RAS组分在PT中均得到明确证明（并且在 行IRPTC），实际的细胞内定位是不完全知道的。 RAS组分的细胞内产生、定位和运输 将通过免疫电子显微镜，共聚焦显微镜， 亚细胞分离加上分子和细胞技术。 第二章： 血管紧张素Ⅱ影响PT溶质转运的机制 Ang II展示了 对水盐运移的双向影响。 Ang II的影响 将使用Na +/H+交换器作为 包括分子生物学和细胞的平行研究中的原型 physiology. 将寻找血管紧张素II反应元件;血管紧张素II对 将描述NHE的mRNA和蛋白质调节[例如，mRNA稳定 状态水平、稳定性和定位;免疫染色强度和 模式[例如，与运输和免疫测定];和细胞信号和 生理学将被定义。 III：Ang II及其自分泌和内分泌 影响，因为这些影响PT功能，如生长和修复，以及蛋白质 加工，假设血管紧张素II调节细胞的生长和修复。 的 血管紧张素II在IRPTC中的功能作用将通过阻断或 刺激RAS组分以剖析自分泌效应。 IRPTC有 细胞内血管紧张素II受体;因此，可能的细胞内加工 将研究血管紧张素原（肾素底物）。

项目成果

Characterization of a putative insulin-responsive element and its binding protein(s) in rat angiotensinogen gene promoter: regulation by glucose and insulin.

大鼠血管紧张素原基因启动子中假定的胰岛素反应元件及其结合蛋白的表征：葡萄糖和胰岛素的调节。

• DOI: 10.1210/endo.142.6.8214
• 发表时间: 2001
• 期刊: Endocrinology.
• 作者: Chen,X;Zhang,SL;Pang,L;Filep,JG;Tang,SS;Ingelfinger,JR;Chan,JS
• 通讯作者: Chan,JS

Rapamycin increases transforming growth factor-beta mRNA expression in immortalized rat proximal renal tubular cells.

雷帕霉素增加永生化大鼠近端肾小管细胞中转化生长因子-β mRNA 的表达。

• DOI: 10.1097/00007890-200201270-00033
• 发表时间: 2002
• 期刊: Transplantation
• 影响因子: 6.2
• 作者: Swinford,RitaD;Pascual,Manuel;Diamant,Daniel;Tang,Shiow-Shih;Ingelfinger,JulieR
• 通讯作者: Ingelfinger,JulieR

Molecular mechanisms of glucose action on angiotensinogen gene expression in rat proximal tubular cells.

• DOI: 10.1046/j.1523-1755.1999.00271.x
• 发表时间: 1999-02
• 期刊: Kidney international
• 影响因子: 19.6
• 作者: Shao-Ling Zhang;J. Filep;J. Filep;J. Filep;Thomas C. Hohman;Thomas C. Hohman;Thomas C. Hohman;S. Tang;S. Tang;S. Tang;J. Ingelfinger;J. Ingelfinger;J. Ingelfinger;J. S. Chan;J. S. Chan;J. S. Chan

Angiotensin II stimulates Pax-2 in rat kidney proximal tubular cells: impact on proliferation and apoptosis.

血管紧张素 II 刺激大鼠肾近端肾小管细胞中的 Pax-2：对增殖和凋亡的影响。

• DOI: 10.1111/j.1523-1755.2004.66008.x
• 发表时间: 2004
• 期刊: Kidney international
• 影响因子: 19.6
• 作者: Zhang,Shao-Ling;Guo,Jun;Moini,Babak;Ingelfinger,JulieR
• 通讯作者: Ingelfinger,JulieR

Immortalized rat proximal tubule cell lines expressing components of the renin-angiotensin system.

表达肾素-血管紧张素系统成分的永生化大鼠近曲小管细胞系。

• 发表时间: 1994
• 期刊: Experimental nephrology
• 作者: Tang,SS;Jung,F;Diamant,D;Ingelfinger,J
• 通讯作者: Ingelfinger,J