Gap Junction Mediated Signaling and Vascular Responses

描述（申请人摘要）：缝隙连接是细胞间的细胞间隙连接簇。 通道，由连接蛋白组成，连接相邻细胞的细胞质 细胞，允许小分子的直接转移。在血管壁， 表达三种连接蛋白（Cx37、Cx40和Cx43），其可介导 内皮细胞、平滑肌细胞之间以及 内皮细胞和平滑肌细胞。这个项目的长期目标是 是了解缝隙连接通讯在调节 血管反应，并确定具体的连接蛋白的贡献。是 认为血管交通是协调血管运动的重要途径， 血管反应，通过允许电和/或化学物质的转移， 信号.两种存活的连接蛋白敲除小鼠系（Cx37 KO和Cx4OKO小鼠）和 先前产生了两种连接蛋白（Cx37/40K0）缺陷的细胞系， 允许测试特定连接蛋白在血管通讯中的作用， 功能在这项研究中，细胞内注射缝隙连接可渗透的 示踪剂用于跟踪内皮、肌内皮和平滑肌细胞的变化。 连接蛋白敲除与野生型血管中的肌肉通讯，而 进行全细胞电压钳以比较离子偶联。的 Cx37和Cx4O相互作用形成异聚体通道的可能性是 通过转染连接蛋白表达载体在细胞培养中进行研究， 单通道录音。Cx37和Cx40在血管紧张素转换中的作用 通过对野生型小鼠进行等长张力测量， 和用血管扩张剂或抗血管炎药治疗的连接蛋白敲除主动脉环。 血管收缩剂Cx37和/或Cx40参与 肌内皮缝隙连接和介导内皮依赖性，NO非依赖性 研究了弛豫响应。因为缝隙连接可能在 维持血管稳态和反应性，更好地了解 血管细胞间通讯可能会带来新的见解和治疗方法 用于动脉粥样硬化、高血压和由血管痉挛引起的心绞痛类型， 冠状血管

DESCRIPTION (Applicant's abstract): Gap junctions are clusters of intercellular channels, composed of connexin proteins, that connect the cytoplasm of adjacent cells, allowing the direct transfer of small molecules. In the vascular wall, three connexins are expressed (Cx37, Cx40, and Cx43) which may mediate communication among endothelial cells, smooth muscle cells, and between endothelial cells and smooth muscle cells. The long-term goal of this project is to understand the role that gap junction communication plays in regulating vascular responses and to define the contributions of specific connexins. It is thought that vascular communication is an important pathway for coordination of vasomotor responses, by allowing for transfer of electrical and/or chemical signals. Two viable connexin knockout mouse lines (Cx37KO and Cx4OKO mice) and a line deficient in both connexins (Cx37/40K0) were previously generated, allowing a test of the role of specific connexins in vascular communication and function. In this study, intracellular injection of gap junction-permeable tracers is used to track changes in endothelial, myoendothelial, and smooth muscle communication in connexin knockout versus wild-type blood vessels, while whole-cell voltage clamp is performed to compare ionic coupling. The possibility that Cx37 and Cx4O interact to form heteromeric channels is investigated in cell culture by transfection of connexin expression vectors and by single channel recordings. The role that Cx37 and Cx40 play in vasomotor responses is examined by performing isometric tension measurements on wild-type and connexin knockout aortic rings treated with a vasodilator or a vasoconstrictor. The possibility that Cx37 and/or Cx40 contribute to myoendothelial gap junctions and mediate endothelium-dependent, NO-independent relaxation responses is investigated. Because gap junctions may be important in maintaining vascular homeostasis and responsiveness, a better understanding of vascular intercellular communication could lead to new insights and treatments for atherosclerosis, hypertension, and types of angina caused by vasospasm of coronary vessels.