GLOMERULAR CAPILLARY WALL--NORMAL AND PATHOLOGIC

蛋白多糖(PG)是细胞外的重要成分。 基质(肾小球基底膜，GBM；系膜基质，MM)，以及 显然是由所有类型的细胞以不同的比例合成的 肾小球，即上皮、内皮和系膜。他们 赋予肾小球电荷和大小选择性属性并维持 它的正直。因此，由于以下原因，PGs的结构混乱 不同类型的肾小球细胞合成不平衡， 会导致细胞外细胞外的解体 基质和蛋白尿。这样的结构性变化在各种不同的地方都可以看到 免疫和非免疫介导的肾炎。我们建议 描述与蛋白多糖相关的致病机制 生物合成，导致这种结构异常通过利用细胞- 生物生化、免疫组织化学和分子生物学 以下四个目标中的技术：目的I.cdna探针 对于大鼠肾小球系膜，将制备硫酸乙酰肝素蛋白多糖(HS-PG)： 随后确定了哪个核苷酸序列&与 HS-PG核心肽的氨基酸序列。目标二。 蛋白多糖生物合成在转录和转录水平上的变化 翻译后水平将在免疫学和 非免疫介导的肾小球肾炎 指明的技术。目标三.各种炎症的影响 介质，如IL-I、PGA2、PGE2、肿瘤坏死因子ROS；以及糖皮质激素 PGs的生物合成将在器官灌流系统中进行研究。 通过以上概述的技术。目标IV.蛋白多糖在 肾小球在体内和体外的发育状态将是 通过扰乱新陈代谢的不同阶段进行研究 木糖苷和嘌呤霉素的生物合成。 有了这些目标，我们预计将描绘出 细胞机制&在前列腺素生物合成的复杂平衡中 通过肾小球的不同细胞类型导致结构性 在不同的细胞外基质中观察到的排列紊乱 肾炎。

Proteoglycans (PGs) are essential components of the extracellular matrices (glomerular basement membrane, GBM; mesangial matrix, MM), and apparently synthesized, in various proportions, by all the cell types o the renal glomerulus, i.e. epithelium, endothelium & mesangium. They impart charge- & size-selective properties to the glomerulus & maintain its integrity. Accordingly, structural derangements of the PGs, due to imbalance in their synthesis by different cell types of the glomerulus, would be expected to result in the disorganization of the extracellular matrices & proteinuria. Such structural alterations are seen in various immunologically & nonimmunologically mediated nephritides. We propose to delineate the pathogenetic mechanisms, relative to the proteoglycan biosynthesis, leading to such structural abnormalities by utilizing cell- biological biochemical, immunohistochemical & molecular biology techniques in the following four objectives: Objective I. cDNA probes for the rat GBM heparan sulfate-proteoglycan (HS- PG) will be prepared: following which nucleotide sequence determined & compared with the aminoacid sequence of the core-peptide of HS-PG. Objective II. Alterations in the proteoglycan biosynthesis at transcriptional & posttranslational levels will be investigated in immunologically & nonimmunologically-mediated glomerular nephritides by utilizing the above indicated techniques. Objective III. Effect of various inflammatory mediators, e,g., IL-I, PGA2, PGE2, TNF ROS; and glucocorticoids on the biosynthesis of PGs will be investigated in an organ perfusion system & by the techniques outlined above. Objective IV. Role of proteoglycans in renal glomerular development in vivo & in vitro states will be investigated by perturbing the metabolism at various steps of their biosynthesis with exposure to xyloside & puromycin. With these objectives we anticipate to delineate the breakdown in the cellular mechanisms & in the intricate balance of the biosynthesis of PGs by the various cell types of the glomerulus which lead to structural derangements in the extracellular matrices as observed in various nephritides.