ROLE OF ICOSANOIDS IN RENAL FUNCTION

在过去的六年中，NAOPH依赖的细胞色素P-450 花生四烯酸的代谢已经变得越来越重要。 该计划项目赠款代表了一种独特的合作 旨在表征该途径的生物化学及其 对肾脏的重要性。 6独立但 提出了以下配套工程：1）交通影响 花生四烯酸P-450代谢物在确定的肾单位节段。 那里 现在有充分的理由相信P-450代谢物具有重要的 对近端小管钠转运的功能影响，器官 近端小管的离子分泌，髓质的盐转运 Henle升支粗，加压素调节水流量 皮质集合小管中的一个 项目1将继续研究 和这些直接的管状作用的机制。 （二） 肾细胞色素P-450花生四烯酸代谢的表征。 本计画将描述花生四烯酸的生物化学特性 在酶学、代谢物形成、结构 在肾脏中的表征、调节和定位。 这些研究对功能研究至关重要。 3)作用 人血小板中的细胞色素P-450花生四烯酸酯代谢物， 他们的聚集。 血小板聚集和释放 生物活性产物在肾脏中起着重要作用， 疾病 根据最近的证据显示， P-450代谢物对血小板聚集的影响，该项目将 鉴定人血小板中P-450氧合产物，测定 它们在血小板脂质中的酯化作用，检查它们对 激动剂诱导的血小板聚集，检查它们从 激活血小板，并确定其机制， 抑制血小板聚集。 4)P-450的体内研究 代谢物。 研究将测试它们对肾功能的影响， 利用大鼠体内清除和微穿刺研究。 关于P-450代谢的深度调节的初步数据， 实验模型，如单侧肾切除术，糖尿病， 怀孕将继续进行。 5)模型细胞的表征 研究细胞色素P-450花生四烯酸代谢物以测试系统 它们对信号转导通路的影响，并确定 是否作为细胞内第二信使。 六、 肾P-450类花生酸的表征和合成， 制定合成代谢物的策略， 用于生物学评价的抑制剂。 我们认为这些项目 代表了技术和调查人员的理想整合， 说明肾脏细胞色素P-450的生物学重要性 花生四烯酸代谢。

Over the past six years the NAOPH dependent cytochrome P-450 metabolism of arachidonic acid has assumed increasing importance. This Program Project Grant represents a unique collaboration designed to characterize the biochemistry of this pathway and its overall importance to the kidney. Six independent but complimentary projects are proposed: 1) Transport effects of arachidonate P-450 metabolites in defined nephron segments. There is now good reason to believe that P-450 metabolites have important functional effects on sodium transport in proximal tubule, organic ion secretion in proximal tubule, salt transport in the medullary thick ascending limb of Henle, and vasopressin modulated water flow in the cortical collecting tubule. Project 1 will pursue the sites and mechanisms of these direct tubular actions. 2) characterization of renal cytochrome P-450 arachidonate metabolism. This project will characterize the biochemistry of arachidonic acid oxidation in terms of enzymology, metabolite formation, structural characterization, regulation, and localization in the kidney. These studies are critical to the functional studies. 3) Role of cytochrome P-450 arachidonate metabolites in human platelets and their aggregation. Platelet aggregation and release of biologically active products plays an important role in renal disease. Based on the recent demonstration of potent effects of a P-450 metabolite on platelet aggregation, this project will identify P-450 oxygenation products in human platelets, determine their esterification in platelet lipids, examine their effects on agonist induced platelet aggregation, examine their release from activated platelet and determine the mechanism by which they inhibit platelet aggregation. 4) In vivo studies of P-450 metabolites. Studies will test their effects on renal function in vivo utilizing clearance and micropuncture studies in the rat. Preliminary data on profound modulation of P-450 metabolism in experimental models such as unilateral nephrectomy, diabetes, and pregnancy will be pursued. 5) Characterization of a model cell system to study cytochrome P-450 arachidonate metabolites to test their effects on signal transduction pathways, and to determine whether they serve as intracellular second messenger. 6) Characterization and synthesis of renal P-450 eicosnoids, development of strategies to synthesize the metabolites and inhibitors for biological evaluation. We feel that these projects represent an ideal integration of techniques and investigators to address the biological importance of renal cytochrome P-450 arachidonate metabolism.