REGULATION OF URINARY ACIDIFICATION

尿液酸化的调节

• 批准号: 3234546
• 负责人: NEIL A KURTZMAN
• 金额: $ 17.53万
• 依托单位: TEXAS TECH UNIVERSITY HEALTH SCIS CENTER
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-01-01 至 1991-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3234546
• 关键词: Anura; Chelonia; acetazolamide; acid base balance; acidity /alkalinity; adenosine triphosphate; aldosterone; alkalosis; amiloride; ammonia; bicarbonates; biological fluid transport; body fluid balance therapy; calcium disorder; chronic renal failure; controlled environment chamber; dietary mineral; dietary trace element; dogs; dopamine receptor; hypercapnia; hyperparathyroidism; intracellular; ion transport; kidney pharmacology; laboratory rabbit; laboratory rat; lithium; longitudinal animal study; membrane permeability; membrane transport proteins; micropuncture; mineralocorticoids; nuclear magnetic resonance spectroscopy; nutrient interaction; nutrition related tag; parathyroid hormones; parathyroidectomy; phosphates; phosphorus metabolism disorders; renal tubular transport; renal tubule; respiratory acidosis; urinary bladder; urine acidity; vanadium

The studies proposed in this application are divided into three sections depending on the technique used. They are all designed to answer fundamental questions concerning the physiology and pathophysiology of distal urinary acidification. The first set of studies uses clearance techniques and will attempt to use the ability to lower the urine pC02 as an index of distal acidification. We believe that the titration of nonbicarbonate buffer consumes C02 and in the absence of bicarbonate buffer lowers the final urine pC02 to a value below that of blood. We also believe that this consumption of C02 can be disclosed in the presence of urinary bicarbonate by the simultaneous infusion of carbonic anhydrase. These studies will also examine the role of aldosterone on both cortical and medullary collecting duct acidification. The second group of studies uses the turtle bladder as a probe. It will attempt to examine the role of transepithelial voltage on carbonic anhydrase-independent acidification in this membrane. We will also attempt to dissect the different transport properties of the granular and mitochondrial rich cells in this membrane. The relationship of voltage to the backleak produced by the antifungal antibiotic amphotericin B will be examined, as will the effect of amiloride on bicarbonate permeability. Finally, the effect of vanadate, a well known inhibitor of proton secretion, on bicarbonate secretion will be examined. The third section of these studies deals with the role of proton ATPase in collecting duct acidification. These studies will test the hypothesis that proton ATPase can be measured in the mammalian collecting tubule and that its activity correlates with the state of acidification in this nephron segment. These studies will make use of the technique of enzyme analysis in in vitro nephron fragments. Taken as a whole, these studies are designed to continue our long-term examination of the forces which control distal urinary acidification under normal and abnormal circumstances.

本应用中提出的研究分为三个部分 取决于所使用的技术。 他们都是为了回答 有关生理和病理生理学的基本问题 尿酸远端。 第一组研究使用许可 技术，并将尝试利用降低尿液PC02的能力 远端酸化指数。 我们相信滴定 非面碳酸盐缓冲液会消耗C02，并且在没有碳酸氢盐缓冲液的情况下 将最终的尿液PC02降低到低于血液的值。 我们也是 认为可以在存在的情况下披露C02的这种消费 碳酸氢盐通过同时输注碳酸酐酶。 这些研究还将检查醛固酮在两种皮质上的作用 和髓质收集导管酸化。 第二组研究 将乌龟膀胱用作探针。 它将尝试检查 在碳赤铁酶独立于酸化酸化上的旋转电压 这个膜。 我们还将尝试剖析不同的运输 该膜中颗粒状和线粒体富细胞的特性。 抗真菌产生的电压与背裂的关系 将检查抗生素两性霉素B，艾米洛德的作用也会 在碳酸氢盐渗透性上。 最后，钒酸盐的效果，一个众所周知的 质子分泌的抑制剂，将检查碳酸氢盐分泌。 这些研究的第三部分涉及质子ATPase在 收集管道酸化。 这些研究将检验以下假设 质子ATPase可以在哺乳动物收集小管中测量 它的活性与该肾单位的酸化状态相关 部分。 这些研究将利用酶分析技术 在体外肾单位碎片中。 从整体上看，这些研究是 旨在继续我们对控制力量的长期检查 在正常和异常情况下尿液酸化。