MEDULLARY CYCLOOXYGENASE PRODUCTS AND RENAL DISEASE

现在很清楚，肾脏疾病的进展不仅涉及 肾小球，但也tubulointerstitial区。 虽然许多肽 生长因子、细胞因子和血管活性激素被认为 在进行性肾单位的发病机制中起重要作用 破坏，花生四烯酸产品可能发挥核心作用， 环氧合酶 因为集合管既是 肾环氧化酶和前列腺素的合成，因为许多 肾损伤的实验模型不仅与 增加肾小球，但也尿环氧合酶产品， 研究集合管前列腺素的作用 在进行性肾衰竭的相关模型中形成。 这项建议 目的是阐明导致肾脏前列腺素合成的因素， 增加后四分之三肾切除术在兔。 研究将 由于我们最近开发了单克隆抗体， 实验室对抗这个物种的集合管将允许 收集管细胞的生化特征， 全肾切除术 使用新鲜免疫切割的细胞以及 将细胞置于原代培养物中，我们将检测前列腺素的合成， 使用免疫沉淀法测量环氧合酶水平， 使用北方印迹分析的信息。 我们还将确定 肾大部切除对P21-ras和P35蛋白表达的影响， 定位于集合管，并似乎与 环氧合酶产物形成的过程。 这些研究报告将 扩展到检查前列腺素水平增加的影响，或 内源性前列腺素合成对细胞外基质抑制作用 由培养的髓质集合管细胞和肾髓质 间质细胞 最后，前列腺素及其作用 类似物对体外培养的集合管和肾髓质生长的影响 将测定间质细胞。 这些研究的目的是 第一次描述了集合管在 肾损伤后产生胰头素及其意义 前列腺素的产生，因为它与功能和结构变化有关 在肾髓质 这些信息应该为以下方面开辟新的途径： 研究肾脏疾病的进展。

It is now clear the progression of renal disease involves not only the glomerulus, but also the tubulointerstitial region. While many peptide growth factors, cytokines, and vasoactive hormones have been postulated to play an important role in the pathogenesis of progressive nephron destruction, there is potentially a central role for arachidonate products of cyclooxygenase. Because the collecting duct is both a major site for renal cyclooxygenase and prostaglandin synthesis and because numerous experimental models of renal injury have been associated with not only increased glomerular, but also urinary cyclooxygenase products, it would appear critical to investigate the role of collecting duct prostaglandin formation in a relevant model of progressive renal failure. This proposal is to elucidate those factors causing renal prostaglandin synthesis to increase after three-quarters nephrectomy in the rabbit. Studies will focus on the rabbit since monoclonal antibodies recently developed in our laboratory against the collecting duct of this species will allow biochemical characterization of collecting duct cells harvested post sub- total nephrectomy. Using both freshly immunodissected cells as well as cells placed in primary culture, we will examine prostaglandin synthesis, measure cyclooxygenase levels using immunoprecipitation, and cyclooxygenase message using norther blot analysis. We will also determine the effects of sub-total nephrectomy on the expression of P21-ras and P35 proteins that localize to the collecting duct and appear to critically interact with the process of cyclooxygenase product formation. These studies will be extended to examine the effects of increased prostaglandin levels or inhibition of endogenous prostaglandin synthesis on extracellular matrix formation by cultured medullary collecting duct cells and renal medullary interstitial cells. Finally, the effects of prostaglandins and their analogues on growth of cultured collecting duct and renal medullary interstitial cells will be determined. It is the goal of these studies to characterize for the first time the role of the collecting duct in generating prostaglandins after renal injury and the significance of this prostaglandin generation as it relates to functional and structural changes in the renal medulla. This information should open up new avenues for investigation of the progression of renal disease.