OXIDATIVE METABOLISM AND TRANSPORT IN RENAL TUBULES

肾小管中的氧化代谢和转运

• 批准号: 3228037
• 负责人: LAZARO J MANDEL
• 金额: $ 21.09万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1980
• 资助国家: 美国
• 起止时间: 1980-04-01 至 1988-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3228037
• 关键词: acetazolamide; acidosis; adenosine diphosphate; adenosine triphosphate; aldosterone; alpha ketoglutarate; aorta; butyrates; cell membrane; cytochrome c; cytochromes; cytoplasm; glucose metabolism; glutamates; kidney metabolism; lactates; mathematical model; membrane permeability; mitochondria; nicotinamide adenine dinucleotide; nonelectrolyte transport; oxidation reduction reaction; oxygen consumption; oxygen transport; p aminohippurate; physical chemical interaction; portal vein; renal cortex; renal tubular transport; saluresis; secretion; solute; succinates; vasopressins

We propose to continue the efforts of the past few years to study a variety of aspects of the interrelationship between metabolism and transport in renal tubules. Many of our recent advances in this area were dependent on the development of a viable rabbit proximal tubule suspension with open lumens and an array of methods to study this preparation. Methods that will continue to be used include: oxygen consumption, rapid potassium uptake, fluorometry, transport in isolated perfused tubules and tubule suspensions, and chemical determinations of cellular adenine nucleotides. We propose to develop methodology for cellular fractionation to separate mitochondrial and cytoplasmic fractions, as well as the use of high performance liquid charomatography (HPLC) for complete nucleotide and specific metabolite measurements in each of these fractions. Standard biochemical assays will still be required for other metabolites. All these techniques will be used to separately probe the metabolic and transport dysfunctions that occur upon phosphate depletion and anoxia. This information is expected to be of clinical relevance, since the added basic knowledge should suggest interventions to ameliorate the dysfunctions, and these will be tested in our preparation. On a more basic level, the kinetic properties of the Na, K-ATPase will be tested as a function of cellular ATP and other nucleotides in the intact renal cell. In addition, we will continue to measure the cytosolic free calcium concentration in renal tubules using the null-point method, first, in an attempt to understand how this concentration is regulated and, ultimately, to determine how this variable affects metabolism and tranport in kidney tubules. Electron probe microanalysis will be performed on samples from kidney tubules, using a new facility being developed in our Department. Initially, the cytoplasmic and mitochondrial levels of calcium will be assayed. The long-term goal is to obtain cellular maps fot Na, K, Cl, Ca, Mg, Pi, and S. Finally, a new preparation will be developed of rabbit thick ascending limb tubules in suspension to study transport and metabolism in this segment. The substrate specificity, hormonal action, loop diuretic effects and anoxia will be particularly studied.

我们建议继续过去几年的努力来研究各种 新陈代谢与运输之间的相互关系方面 肾小管。 我们最近在这一领域的许多进步取决于 开放的可行兔子近端小管悬浮液的开发 流明和一系列研究这种制剂的方法。 方法 将继续使用包括：氧气消耗，快速钾 摄取，荧光测定法，孤立的灌注小管和小管中的传输 悬浮液和细胞腺嘌呤核苷酸的化学测定。 我们建议开发用于细胞分馏的方法，以分离 线粒体和细胞质级分，以及高含量 用于完整核苷酸和 这些部分的特定代谢物测量值。 标准 其他代谢产物仍然需要生化测定。 所有这些 技术将用于单独探测代谢和运输 磷酸盐耗竭和缺氧时发生功能障碍。 这 预计信息将具有临床相关性，因为增加了基本 知识应建议改善功能障碍的干预措施，并 这些将在我们的准备工作中进行测试。 在更基本的层面上， Na，k-atpase的动力学特性将被测试 完整肾细胞中的细胞ATP和其他核苷酸。 此外， 我们将继续测量中的无胞质钙浓度 首先，使用NULL点方法的肾小管小管 了解如何调节这种集中度，并最终 确定该变量如何影响肾脏的新陈代谢和转运 小管。 电子探针微分析将对来自 肾小管，使用我们部门正在开发的新设施。 最初，钙的细胞质和线粒体水平将是 测定。 长期目标是获得细胞图fot fot fot na，k，cl，ca， MG，Pi和S。最后，将开发出新的兔子制剂 悬浮液中的较厚上升的肢体小管研究运输和 该细分市场的代谢。 底物特异性，激素作用， 循环利尿作用和缺氧将特别研究。