Gap Junction Mediated Signaling and Vascular Responses

描述(申请人摘要)：缝隙连接是细胞间的簇 由连接蛋白组成的通道，连接相邻的细胞质 细胞，允许小分子的直接转移。在血管壁上， 表达了三种连接蛋白(Cx37、Cx40和Cx43)，它们可能介导 内皮细胞、平滑肌细胞之间以及血管内皮细胞和血管内皮细胞之间的通讯 内皮细胞和平滑肌细胞。这个项目的长期目标是 就是了解缝隙连接通讯在调节 血管反应和确定特定的连接蛋白的作用。它是 认为血管沟通是协调的重要途径 血管运动反应，通过允许电和/或化学物质的转移 信号。两个可存活的连接蛋白基因敲除小鼠系(Cx37KO和Cx4OKO小鼠)和 先前产生了两个连接蛋白缺失的品系(Cx37/40K0)， 允许测试特定的连接蛋白在血管通讯中的作用 功能。在本研究中，细胞内注射的缝隙连接是可渗透的 示踪剂用于跟踪内皮细胞、肌内皮细胞和平滑细胞的变化 连接蛋白基因敲除与野生型血管的肌肉通讯 为了比较离子耦合，采用了全电池电压钳技术。这个 Cx37和Cx4O相互作用形成异构体通道的可能性是 连接蛋白表达载体和连接蛋白在细胞培养中的研究 通过单通道记录。Cx37和Cx40在血管运动中的作用 通过对野生型进行等长张力测量来检查响应 和连接蛋白基因敲除的主动脉环使用血管扩张剂或 血管收缩药。Cx37和/或Cx40对 肌内皮细胞缝隙连接及其介导的内皮依赖性和非依赖性 对松弛响应进行了研究。因为缝隙连接可能在 维持血管动态平衡和反应性，更好地理解 血管细胞间通讯可能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 冠状动脉血管。

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.