ROLE OF BRADYKININ RECEPTORS IN HUMAN LUNG FIBROBLASTS

这项提案的目标是：(A)确定 肽介质缓激肽与其受体相互作用，以及(B) 发现成纤维细胞对特定受体靶细胞的反应 在间质结缔组织中。初步研究将在#年进行。 表达缓激肽受体的特定培养细胞系统， 包括人肺成纤维细胞株W1-38和IMR-90，另外 我们将培养的人肺和皮肤成纤维细胞的菌株，以及 建立了HSDM1C1小鼠纤维肉瘤细胞系。受体数量和 亲和力将由放射性配基结合和结构/活性决定 天然缓激肽相关肽，合成类似物， 将对受体拮抗剂进行评估。受体脱敏将 探索环核苷酸的相对贡献，官能团或 受体与相关通路的物理解偶联和靶细胞 结合配体的降解，可能是通过与受体相关的机制。 待定义的目标小区响应包括数量和类型 通过环氧合酶和脂氧合酶产生的花生四烯酸衍生物 途径、环核苷酸水平的变化和总细胞的变化 蛋白质合成。该项目将评估特定的 缓激肽受体可能与特定的靶细胞反应相关， 例如增加蛋白质合成或产生具有特征的 与炎症或创伤相关的次级介质。这些研究将 然后扩展到新鲜分离的人肺成纤维细胞和完整的肺 组织切片。这项拟议的研究将定义 缓激肽受体介导的生物学活性。它将寻求 确定它们在皮肤和肺成纤维细胞中是否相似，或者它们是否 不同的肺成纤维细胞在某种程度上促进了发育 和人类肺损伤的进展。

The goals of this proposal are to define (a) the mechanisms by which the peptide mediator bradykinin interacts with its receptors, and (b) the response of specific receptor-bearing target cells: the fibroblasts found in interstitial connective tissue. Initial studies will be carried out in specific cultured cell systems which express bradykinin receptors, including the human lung fibroblast strains W1-38 and IMR-90, additional strains of both human lung and skin fibroblasts which we will develop, and the HSDM1C1 murine fibrosarcoma established cell line. Receptor number and affinity will be determined by radioligand binding, and structure/activity relationships for natural bradykinin-related peptides, synthetic analogs, and receptor antagonists will be assessed. Receptor desensitization will be explored for relative contributions of cyclic nucleotides, functional or physical uncoupling of receptor from linked pathways, and target cell degradation of bound ligand, possibly by a receptor-associated mechanism. The target cell responses to be defined include amount and type of arachidonate derivatives produced via the cyclo-oxygenase and lipoxygenase pathways, changes in cyclic nucleotide levels and alterations in total cell protein synthesis. This project will assess whether a particular bradykinin receptor may correlate with a specific target cell response, such as increased protein synthesis or production of characteristic secondary mediators related to inflammation or trauma. These studies will then be extended to freshly-isolated human lung fibroblasts and intact lung tissue slices. The proposed research will define the mechanisms of bradykinin receptor-mediated biologic activities. It will seek to determine if these are similar in skin and lung fibroblasts, or if they differ in lung fibroblasts in some way which contributes to the development and progression of human lung injury.