FIBROBLAST HETEROGENEITY IN NORMAL AND FIBROTIC LUNG

我们将确定是否从正常肺组织中分离大鼠肺成纤维细胞， 博来霉素处理的大鼠作为异质细胞群存在 不同的胶原蛋白合成率。 主要目标是 为胶原代谢的差异提供了分子基础， 正常和纤维化大鼠肺成纤维细胞亚群。 母 培养物将使用细胞分离成成纤维细胞亚群， 分拣员。 分离的细胞将通过测定 各种胶原合成参数，包括细胞和 多聚体I型和III型前胶原合成，分泌， 积累和降解，细胞浓度的类型 I型和III型前胶原mRNA和稳态水平 细胞核、多核糖体后细胞质和 多核糖体 总细胞的合成和降解速率 将测定前胶原mRNA种类。 积累 新合成的前胶原mRNA的亚细胞 还将确定分数。 I型和III型前胶原 mRNA转录将通过测定mRNA的量来评估。 I型和III型前胶原hnRNA的表达，以及这些表达的能力， 细胞核在体外合成可降解的I型和III型 前胶原mRNA。 核前胶原mRNA的合成 将通过将成纤维细胞与（3H）尿苷孵育 很短的时间。 这些mRNA的转运速率 进入细胞质的物种将被确定。 我们还将 确定I型和III型可能的异敏性 糖皮质激素的成纤维细胞亚群中的前胶原合成 和博莱霉素。 这些研究将确定胶原蛋白 正常和纤维化成纤维细胞亚群的合成率 肺。 一个成纤维细胞亚群可能贡献更多的胶原蛋白 在纤维化肺病中的作用更大。 这可以提供 这些信息将有助于治疗干预。

We will determine if rat lung fibroblasts isolated from normal and bleomycin-treated rats exist as a heterogeneous group of cells with different collagen synthetic rates. The major objective is to provide molecular bases for differences of collagen metabolism in normal and fibrotic rat lung fibroblast subpopulations. The parent cultures will be separated into fibroblast subsets using a cell sorter. The isolated cells will be characterized by determining various collagen synthetic parameters including cellular and polysomal type I and type III procollagen synthesis, secretion, accumulation and degradation, the cellular concentrations of type I and type III procollagen mRNAs and the steady state levels of procollagen mRNAs in nuclei, the post-polysomal cytoplasm and polysomes. The synthetic and degradative rates of total cellular procollagen mRNA species will be determined. The accumulation of newly synthesized procollagen mRNAs in the subcellular fractions will also be determined. Type I and type III procollagen mRNA transcription will be assessed by determining the amounts of type I and type III procollagen hnRNAs and the ability of these nuclei in vitro to synthesize hydridizable type I and type III procollagen mRNAs. The synthesis of nuclear procollagen mRNAs will be determined by incubating fibroblast with (3H) uridine for short periods of time. The rates of transport of these mRNA species into the cytoplasm will be determined. We will also determine the possible heterosensitivity of type I and type III procollagen synthesis in the fibroblast subsets of glucocorticoids and bleomycin. These studies will determine the collagen synthetic rates in fibroblast subsets from normal and fibrotic lung. One fibroblast subpopulation may contribute more collagen in fibrotic lung disease than another subset. This may provide information which will be useful for therapeutic intervention.