LUNG VASCULAR & CELLULAR ACTIONS OF C3A, C5A, & FMLP

成人呼吸窘迫综合征(ARDS)的特征 通过肺血管收缩和细胞积聚 和肺实质内富含蛋白质的液体。这个 这些异常的机制尚不清楚。C3a和 补体激活的过敏性毒素产物C5a，以及 甲酰化寡肽细菌产品(例如甲酰 蛋氨酸-亮氨酸-苯丙氨酸；fMLP)可能在 这些异常的发展。在本提案中，我们将 研究补体C3a、C5a和fMLP在体外培养中的作用 肺动脉节段和肺巨噬细胞 兔子。这个项目的具体目标是：1.确定是否 C3a、C5a、它们的Des Arg衍生物或fMLP收缩隔离 兔肺动脉环节段。我们将构建剂量- 反应曲线，并评估组织脱敏，协同作用， 以及这些多肽之间的交叉反应。2.确定 通过使用药物抑制剂，如果这些药物的作用 多肽可归因于组胺或 花生四烯酸代谢。3.确定 血管内皮细胞在这些多肽对血管内皮细胞的作用 通过测试其对节段的影响来确定肺动脉节段 它们已经接受了内皮的机械剥离。4.至 在肺组织中识别这些多肽的受体 C3a、C5a和fMLP的荧光探针。5.分析 物理参数、配体结合特性和官能团 肺巨噬细胞的特性 多参数流式细胞术。这些研究将拓宽我们的 了解细胞和血管对C3a、C5a和 FMLP，并可能导致开发出更有效的 ARDS的治疗方式。

The adult respiratory distress syndrome (ARDS) is characterized by pulmonary vasoconstriction as well as accumulation of cells and protein-rich fluid within the lung parenchyma. The mechanisms of these abnormalities are not understood. C3a and C5a, the anaphylatoxin products of complement activation, and formaylated oligopeptide bacterial products (e.g. formyl methionine-leucine-phenylalanine; fMLP) may be important in the development of these abnormalities. In this proposal we will investigate the actions of C3a, C5a, and fMLP on isolated pulmonary artery segments and pulmonary macrophages from rabbits. The specific aims of this project are: 1. To determine if C3a, C5a, their des arg derivatives, or fMLP constrict isolated rabbit pulmonary artery ring segments. We will construct dose- response curves, and evaluate tissue desensitization, synergism, and cross-reactivity between these peptides. 2. To determine through the use of pharmacologic inhibitors if the actions of these peptides are attributable to the release of histamine or arachidonic acid metabolities. 3. To determine the role of endothelium in the actions of these peptides on isolated pulmonary artery segments by testing their effects on segments which have undergone mechanical denuding of endothelium. 4. To identify receptors for these peptides in pulmonary tissues utilizing fluorescent probes for C3a, C5a, and fMLP. 5. To analyze physical parameters, ligand binding characteristics, and functional properties of pulmonary macrophages through the use of multiparameter flow cytometry. These studies will broaden our understanding of cellular and vascular responses to C3a, C5a, and fMLP, and may result in the development of more effective therapeutic modalities for ARDS.