Calcium wave propagation along microvascular endothelial tubes

钙波沿微血管内皮管传播

• 批准号: 8203129
• 负责人: Matthew John Socha
• 金额: $ 4.84万
• 依托单位: UNIVERSITY OF MISSOURI-COLUMBIA
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8203129
• 关键词: ATP phosphohydrolase; Abbreviations; Abdominal Muscles; Acetylcholine; Address; Affect; Agonist; Arteries; Atherosclerosis; Behavior; Blood Vessels; Blood flow; Calcium Oscillations; Caliber; Cell membrane; Cells; Characteristics; Coupled; Development; Diabetes Mellitus; Digestion; Disease; Dyes; Endoplasmic Reticulum; Endothelial Cells; Endothelium; Endothelium-Dependent Relaxing Factors; Event; Exercise; Fatigue; Gap Junctions; Goals; Gold; Hypertension; Individual; Inositol; Ischemia; Knowledge; Laboratories; Lead; Length; Metabolic; Microcirculation; Microdissection; Modeling; Mus; Nature; Nitric Oxide; Nutrient; Oxygen; Perfusion; Physiological; Preparation; Process; Production; Receptor Activation; Regulation; Relaxation; Reperfusion Therapy; Research; Research Project Grants; Resistance; Role; Signal Pathway; Signal Transduction; Site; Skeletal Muscle; Smooth Muscle Myocytes; Solutions; Source; Stimulus; Testing; Tissues; Travel; Tube; Vascular Diseases; Vascular Endothelial Cell; Vasodilation; Work; arteriole; base; extracellular; feeding; improved; insight; intercellular communication; novel; novel strategies; novel therapeutic intervention; pressure; prevent; receptor; research study; response; tripolyphosphate

DESCRIPTION (provided by applicant): The long-term research goals of our laboratory center on defining signaling events in the microcirculation that underlie the control of oxygen and nutrient delivery to tissue with an emphasis on skeletal muscle during exercise. My working hypothesis is that the local control of blood flow reflects the coordination of activity among endothelial cells (ECs) and smooth muscle cell (SMCs) of arterioles and feed arteries (FA) that comprise microvascular resistance networks. When delivered to a discrete site on an arteriole or FA, acetylcholine (ACh; the "gold standard" endothelium-dependent vasodilator) initiates a Ca+2 wave that travels from EC to EC for hundreds of microns along the intima to promote relaxation of surrounding SMCs by releasing nitric oxide. However little is known of how calcium waves are initiated or propagated in the microcirculation. To directly address this question, I have developed the intact "endothelial tube" preparation from mouse abdominal muscle feed arteries as a unique model to study the nature of Ca+2 waves independent from the influence of blood flow, transmural pressure, or surrounding SMCs and tissue. Intact microvascular endothelial tubes (diameter, 50-80 5m; length, 1-2 mm) are isolated using microdissection of FA followed by partial enzymatic digestion and gentle trituration. Preliminary studies with dye transfer confirm that ECs throughout the tube are well-coupled through gap junctions and generate robust Ca+2 waves in response to ACh that can propagate more than 500 5m along the tube. My research is focused on understanding how these Ca+2 waves are initiated and how they actually propagate from EC to EC. AIM 1 will identify the source(s) of Ca+2 for wave initiation and propagation by preferentially inhibiting internal release of Ca+2 from the endoplasmic reticulum (ER) and/or its influx across the plasma membrane. AIM 2 will investigate how partial depletion or overloading of intracellular Ca+2 stores affects the initiation and propagation of Ca+2 waves. Resolving the role(s) of intra- and extracellular Ca+2 sources in producing waves will provide new insight concerning how these signaling pathways may contribute to the local regulation of blood flow. In turn, this knowledge will lead to a better understanding of how intrinsic Ca+2 signaling pathways may be altered during such conditions as atherosclerosis, diabetes, hypertension, and ischemia. My overall goal is to apply the findings of this research to the development of novel strategies for treating vascular disease in which tissue perfusion is impaired. PUBLIC HEALTH RELEVANCE: Relevance Blood flow throughout the body is compromised in many diseased states. Healthy endothelial cells promote flow by relaxing blood vessels but are disturbed in diseased states in ways that are not well understood. Research to be performed in this application will provide important new insight into key regulatory processes that endothelial cells use to relax blood vessels. This information will further our understanding how disease disrupts these essential processes and thereby identify new therapeutic approaches for treating vascular disease to improve blood flow throughout the body.

描述（由申请人提供）：我们实验室中心在微循环中定义信号事件的长期研究目标，该目标是控制氧气和营养物向组织的控制，并强调运动过程中骨骼肌。我的工作假设是，血液流动的局部控制反映了动脉和动脉（FA）的内皮细胞（EC）和平滑肌细胞（SMC）之间的活性的协调，包括包括微血管抗性网络。当将乙酰胆碱（ACH；“金标准”内皮依赖性血管扩张剂）送到动脉或FA上的离散部位时，会引发一个Ca+2波，该波浪从EC到EC从EC转移到EC沿着沿着内膜的数百微米，以通过释放一氮氧化物来促进周围SMC的放松。然而，对微循环中如何启动或传播钙波如何鲜为人知。为了直接解决这个问题，我开发了从小鼠腹部肌肉喂养动脉的完整“内皮管”制备，作为一种独特的模型，可以研究CA+2波的性质，而不是血液流动，透射压力或周围SMC和组织的影响。完整的微血管内皮管（直径，50-80 5m；长度为1-2 mm）是通过FA的微分辨率分离的，然后是部分酶促消化和温和的三次。对染料转移的初步研究证实，整个管中的EC通过间隙连接很好地耦合，并对ACH产生强大的Ca+2波，该波响应于ACH，可以沿着管传播超过500 5M。我的研究集中在理解这些CA+2波如何启动以及它们如何从EC到EC的实际传播。 AIM 1将通过优先抑制内质网（ER）（ER）（ER）和/或其跨质膜的涌入来识别波启动和传播的Ca+2的来源。 AIM 2将研究细胞内Ca+2商店的部分耗竭或过载如何影响Ca+2波的启动和传播。解决细胞内和细胞外Ca+2源在产生波中的作用将提供有关这些信号通路如何有助于局部血液流动调节的新见解。反过来，这些知识将更好地理解在动脉粥样硬化，糖尿病，高血压和缺血等条件下的内在CA+2信号通路。我的总体目的是将这项研究的发现应用于治疗血管疾病的新策略的发展，其中组织灌注受损。 公共卫生相关性：在许多患病状态下，整个身体的相关性血流受到损害。健康的内皮细胞通过放松血管来促进流动，但在患病状态下以无法理解的方式受到干扰。在本应用中进行的研究将为内皮细胞用于放松血管的关键调节过程提供重要的新见解。这些信息将进一步理解疾病如何破坏这些基本过程，从而确定治疗血管疾病以改善整个体内血液流动的新治疗方法。