Control of Microcirculatory Exchange Function

描述(申请人提供)：微血管通透性增加是炎症的标志。以往的研究主要集中在如何预防炎症条件下通透性升高的发生和维持。。我们建议检验这一中心假设，即微血管通透性是由平衡信号机制调节的，这些信号机制分别通过增强通透性或屏障属性来维持动态平衡。我们将研究eNOS易位作为刺激高通透性的机制，以及在早期炎症阶段抑制高通透性的机制。我们将在内皮细胞和横纹肌中研究这些过程。我们假设内皮型一氧化氮合酶的易位对于在通透性的效应器上或附近实现有效的一氧化氮浓度是必要的。我们还假设，在高通透性反应的峰值或附近，内皮(或组织)开始了一个过程，以灭活或逆转高通透性，并恢复微血管壁的生理屏障特性。我们进一步提出，小的GTP结合蛋白EPAC/Rap-1作为“屏障增强因子”参与了高通透性失活/逆转过程。具体的假设和需要检验的具体目标是：具体的假设1。eNOS移位到胞浆(非高尔基体胞浆室)是内皮调节微血管通透性的一个步骤。目的1.探讨内皮型一氧化氮合酶易位与血管内皮细胞和微血管通透性调节的关系。特定假设2：cAMP通过EPAC失活或逆转激动剂诱导的高通透性。特异性AIM 2.1研究高通透性的定时失活/逆转。特定的AIM 2.1。目的：确定刺激EPAC是否逆转(失活)激动剂诱导的高通透性。我们将应用活体显微镜结合计算机辅助图像分析和分子生物学方法来阐明假设的机制。与公共卫生相关：更好地了解炎症过程中高通透性与其“生理性”失活或逆转之间的分子机制和时机，应为促进高通透性失活或逆转提供机会之窗，以预防(微)血管疾病中的过度浮肿和间隔室综合征等并发症。

DESCRIPTION (provided by applicant): Increased microvascular permeability is a hallmark of inflammation. Previous research has focused on how to prevent the onset and the maintenance of the elevated permeability under inflammatory conditions. . We propose to test the central hypothesis that Microvascular permeability is regulated by counterbalancing signaling mechanisms that maintain homeostasis by enhancing permeability or barrier properties, respectively. We will investigate eNOS translocation as a mechanism that stimulates hyperpermeability and mechanisms that inactivate hyperpermeability in the early inflammatory phase. We will study these processes in endothelial cells and in striated muscle. We hypothesize that eNOS translocation is necessary to achieve effective NO concentrations at or near the effectors for permeability. We also hypothesize that at or near the peak of the hyperpermeability response, the endothelium (or tissue) begins a process to inactivate or reverse hyperpermeability and restore the physiological barrier properties of the microvascular wall. We further propose that the small GTP-binding proteins Epac/Rap-1 serve as `Barrier Enhancing Factors' and participate in the hyperpermeability-inactivation/reversal process. The Specific Hypotheses and Specific Aims to be tested are: SPECIFIC HYPOTHESIS 1. eNOS translocation to cytosol (non-Golgi cytosol compartment) is a step in endothelial regulation of microvascular permeability. SPECIFIC AIM 1. To investigate the relationship between eNOS translocation and regulation of endothelial and microvascular permeability. SPECIFIC HYPOTHESIS 2: cAMP via Epac inactivates or reverses agonist-induced hyperpermeability. SPECIFIC AIM 2.1 To investigate the timed inactivation/reversal of hyperpermeability. SPECIFIC AIM 2.1. To determine whether or not stimulation of Epac reverses (inactivates) agonist-induced hyperpermeability. We will apply intravital microscopy in conjunction with computer-assisted image analysis and molecular biology approaches to elucidate the postulated mechanisms. PUBLIC HEALTH RELEVANCE: A better understanding of the molecular mechanisms and of the timing between hyperpermeability and its "physiological" inactivation or reversal in inflammatory processes should provide a window of opportunity for promoting inactivation or reversal of hyperpermeability to prevent complications such as excessive edema and compartment syndrome in (micro)vascular disease.