VASODILATION AND GUANYLATE CYCLASE REGULATION

描述：该项目的长期目标是确定和 阐明参与调控的信号转导机制 肺血管紧张性调节蛋白的产生 细胞内松弛介质cGMP通过调节可溶性 形成对各种氧化还原关系的综合理解 这些过程与活性氧的新陈代谢相互作用 一氧化氮(NO)在肺血管张力调节中的作用 涉及sGC调节的机制。首席调查员 建议系统地评估监管sGC的相互作用 肺动脉平滑肌的活动及其在调控中的作用 牵涉的力量：(1)内源性血管平滑的潜在作用 肌肉氧化还原系统包括胞浆NAD和NADP，谷胱甘肽， 微粒体和线粒体的电子传递，重点是 确定H_2O_2、O_2、-和血红素在sGC上的氧化还原状态是否 这些过程控制活动的中心机制 SGC与血管张力的关系；(2)这些氧化还原的关系 系统和NO/O2-相互作用，重点是确定 硫醇亚硝化是一个重要的信号传递过程，以及(3)评估 细胞氧化还原系统之间的相互作用如何被检测，反应性 O2物种和NO衍生物种有助于引发音调反应 通过PO2的变化，重点确定sGC的调制是否 活性是主要的信号转导机制， 观察到的反应。这项提案中的大部分工作将 还侧重于发展对功能和重要性的理解 NADH-细胞色素b558O2-产生电子传递链，其中 调查人员在他们最近对这个项目的工作中发现 在小牛的肺动脉平滑肌中。这个产氧系统 似乎既是内源性活性氧物种的主要来源，也是 发挥PO2传感器的作用，调节sGC活性。海流 提案将使用分离的小牛肺动脉进行音调研究 用机械探针和内源活性O2的测量 物种和cGMP的产生，以及动脉平滑肌亚细胞 用于识别产生激活剂和氧化还原系统的氧化还原系统的组分 SGC的抑制剂。本建议书中审查的流程可 有助于进一步了解氧诱导调节的各个方面 在正常生理状态下的肺循环 循环暴露与肺血管病理生理相关 随着活性氧和NO衍生物种的形成(如急性 肺损伤/ARDS、缺血再灌注、高血压等)。

DESCRIPTION: The long-term goals of this project are to identify and elucidate the signal transduction mechanisms involved in the control of pulmonary vascular tone mediated by modulation of the production of the intracellular mediator of relaxation, cGMP, via regulation the soluble form of an integrated understanding of how various redox-related processes interact with the metabolism of reactive oxygen species and nitric oxide (NO) in the control of pulmonary vascular tone through mechanisms involving the regulation of sGC. The principal investigator proposes to systematically evaluate interactions that regulate sGC activity and its role in the control of pulmonary arterial smooth muscle force involving: (1) the potential role of endogenous vascular smooth muscle redox systems including cytosolic NAD and NADP, glutathione, microsomal and mitochondrial electron transport, with a focus on determining if H2O2, O2.- and the redox status of the heme on sGC are the central mechanisms through which these processes control the activity of sGC and vascular tone, (2) the relationships between these redox systems and the NO/O2.- interaction, with a focus on determining if thiol nitrosation is an important signaling process, and (3) to evaluate how interactions between the cellular redox systems examined, reactive O2 species and NO-derived species contribute to tone responses elicited by changes in PO2, with a focus on determining if the modulation of sGC activity is the primary signal transduction mechanism mediating responses that are observed. Much of the work in this proposal will also focus on developing an understanding of function and importance of NADH-cytochrome b558 O2.- producing electron transport chain, which the investigators have discovered during their recent work on this project in calf pulmonary arterial smooth muscle. This O2.- producing system seems to both be a major source of endogenous reactive O2 species and functions as a PO2 sensor that regulates sGC activity. The current proposal will employ isolated calf pulmonary arteries for tone studies with mechanistic probes, and measurements of endogenous reactive O2 species and cGMP production, and arterial smooth muscle subcellular fractions to identify the redox systems which generate activators and inhibitors of sGC. The processes examined in this proposal may contribute to further understanding aspects of oxygen-elicited regulation of the pulmonary circulation during normal physiology and when this circulation is exposed to pulmonary vascular pathophysiology associated with the formation of reactive oxygen and NO-derived species (e.g. acute lung injury/ARDS, ischemia reperfusion, hypertension, etc.).