LEUKOTRIENES AND SLOW REACTING SUBSTANCE OF ANAPHYLAXIS

描述：(改编自申请人的摘要)。白三烯是 花生四烯酸酶促氧化衍生的脂质介质 由5-脂氧合酶(5-LO)催化。对这些分子的兴趣源于 它们在引起中性粒细胞趋化(LTB4)和 支气管平滑肌收缩(LTC4)。根本问题依然存在 关于它们的生物合成和代谢，这些都是 建议的工作。这个项目由四个主要目标组成。第一个目标 将利用质谱学(MS)进行结构分析 人类尿液中LTB4主要代谢物的特性。A MS 将开发定量分析来评估体内生物合成和 LTB4进入循环的正常速率。第二个目标是评估 不耐受哮喘患者体内LTC4和LTB4的生物合成 通过定量分析每个二十烷类化合物的尿代谢物来获得阿司匹林。 LTB4的生物合成涉及失活的5-LO和LTA4水解酶 通过导致共价结合的基于机制的自杀反应 指酶的亲电性二十烷基类中间体。LTA4还结合了 与人血清白蛋白共价，人血清白蛋白是这种三烯的载体蛋白 环氧化物。该应用程序的第三个目标是利用电喷雾串联MS 和MALDI-TOF MS，以确定共价连接的位置和 蛋白质结合脂的结构。预计这样的信息 将提供对自杀失活的机制和 特定氨基酸对催化事件的重要性 第四个目标是研究自分泌和旁分泌效应。 LTB4对白三烯生物合成和代谢的影响。它们的作用机制 细胞外LTB4可调控中性粒细胞LTB4的生物合成 调查过了。LTB4已被认为通过以下途径增加LTB4的代谢 与核过氧化体增殖激活的相互作用 受体(PPARpha)，并通过这一机制限制促炎 LTB4的特性。LTB4的这一假定效应将在#年进行调查。 通过分析肝细胞和其他细胞的动力学和程度 白三烯代谢。对发生的代谢事件的理解 对于理解这些分子在体内发挥的作用是必不可少的 发炎。

DESCRIPTION: (Adapted from the applicant's abstract). Leukotrienes are lipid mediators derived form arachidonic acid by enzymatic oxidation catalyzed by 5-lipoxygenase (5-LO). Interest in these molecules stems from their potent activities in causing neutrophil chemotaxis (LTB4) and bronchial smooth muscle constriction (LTC4). Fundamental questions remain concerning their biosynthesis and metabolism and these are the focus of the proposed work. This project consists of four major goals. The first goal will be to utilize mass spectrometry (MS) for the structural characterization of the major human urinary metabolites of LTB4. A MS quantitative assay will be developed to asses in vivo biosynthesis and normal entry rate of LTB4 into the circulation. The second goal is to asses LTC4 and LTB4 biosynthesis in asthmatic patients that are intolerant to aspirin by quantitative analysis of urinary metabolites for each eicosanoid. LTB4 biosynthesis involves 5-LO and LTA4 hydrolase that are inactivated through a mechanism based suicide reaction that results in covalent binding of an electrophilic eicosanoid intermediate to the enzyme. LTA4 also binds covalently to human serum albumin, a carrier protein for this triene epoxide. The application's third goal is to utilize electrospray tandem MS and MALDI-TOF MS in order to determine the site of covalent attachment and structure of the protein bound lipid. It is expected that such information will provide insights into the mechanism of suicide inactivation and the importance of specific amino acids to the catalysis event The fourth goal will be to investigate the autocrine and paracrine effects of LTB4 on leukotriene biosynthesis and metabolism. The mechanisms by which extracellular LTB4 can modulate neutrophil LTB4 biosynthesis will be investigated. LTB4 has been suggested to increase LTB4 metabolism through the interaction with the nuclear peroxisomal proliferation activating receptor (PPARalpha) and by this mechanism, limit the proinflammatory properties of LTB4. This putative effect of LTB4 will be investigated in hepatocytes and other cells by analysis of both kinetics and extent of leukotriene metabolism. An understanding of the metabolic events occurring in vivo is essential to an understanding of the role these molecules play in inflammation.