Control of Microcirculatory Exchange Function

描述（由申请人提供）：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。我们建议验证微血管通透性是由平衡信号机制调节的中心假设，这些信号机制分别通过增强通透性或屏障特性来维持体内平衡。我们将研究eNOS易位在炎症早期刺激高渗透性和抑制高渗透性的机制。我们将在内皮细胞和横纹肌中研究这些过程。我们假设eNOS易位对于在渗透性效应物处或附近达到有效的NO浓度是必要的。我们还假设，在高渗透性反应的峰值或接近峰值时，内皮细胞（或组织）开始一个灭活或逆转高渗透性的过程，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。需要检验的具体假设和具体目标有：eNOS易位到细胞质（非高尔基细胞质室）是微血管通透性内皮调节的一个步骤。具体目标1。探讨eNOS易位与内皮和微血管通透性调节的关系。特异性假设2:cAMP通过Epac使激动剂诱导的高渗透性失活或逆转。2.1研究高通透性的时间失活/逆转。具体目标2.1。确定Epac刺激是否逆转（灭活）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。公共卫生相关性：更好地了解炎症过程中高渗透性及其“生理”失活或逆转之间的分子机制和时间，应该为促进高渗透性的失活或逆转提供机会，以预防（微）血管疾病中的过度水肿和室室综合征等并发症。

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.