Regulation Microvascular Smooth Muscle Ca2+ & BK+ ECM-Integrin-Cytoskeletal Axis

调节微血管平滑肌 Ca2

• 批准号: 7918615
• 负责人: Michael John Davis
• 金额: $ 41.5万
• 依托单位: UNIVERSITY OF MISSOURI-COLUMBIA
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-03-22 至 2015-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7918615
• 关键词: Actinin; Adhesions; Affect; Agonist; Atherosclerosis; Binding; Blood Pressure; Blood Vessels; Blood flow; CBL gene; Calcium-Activated Potassium Channel; Caliber; Cell membrane; Cell-Matrix Junction; Cells; Chemosensitization; Chronic; Collagen; Contracts; Diabetes Mellitus; Dilatation - action; Disease; Extracellular Matrix; Extracellular Matrix Proteins; Felis catus; Fibronectins; Focal Adhesions; Inflammation; Inflammatory; Injury; Integrins; Ion Channel; Ions; Knowledge; Mechanics; Mediating; Metabolic; Methods; Movement; Mus; Pathway interactions; Phosphoric Monoester Hydrolases; Phosphorylation; Physiological; Property; Proteins; Rattus; Regulation; Resistance; Role; Signal Transduction; Site; Skeletal Muscle; Smooth Muscle; Smooth Muscle Myocytes; Stretching; Tail; Talin; Testing; Tissues; Transgenic Mice; Vascular Diseases; Vascular remodeling; Vasoconstrictor Agents; Vasodilation; Vasodilator Agents; arteriole; constriction; human BCAR1 protein; insight; integrin-linked kinase; large-conductance calcium-activated potassium channels; mouse model; novel therapeutics; osteopontin; patch clamp; paxillin; pressure; protein expression; receptor; relating to nervous system; response; src-Family Kinases; transmission process; voltage

Interactions between vascular integrins and ECM components of the blood vessel wall are important determinants of arteriolar tone and blood flow control. In Project 2, we focus on two aspects of vascular function in which ECM-integrin interactions acutely regulate vascular tone: 1) mechanotransduction of intravascular pressure through voltage-gated, L-type Ca^* channels (CBL) and BK (large-conductance calcium-activated K*) channels, and 2) the effects of biologically active matricryptins (i.e., proteolytic fragments of ECM proteins with vasoactive properties). The central hvpothesis of Project 2 is that a5B1 inteqrin plavs a critical role in mediatinq the transduction of physiological stretch to mVSM ion channels to enhance mvoqenic tone, while avB3 inteqrin functions as a matricryptin receptor to inhibit myoqenic tone and initiate vasodilation in response to vessel wall iniurv. The hypothesis will be tested using patch-clamp methods to record CaL and BK (large-conductance calcium-activated K* channel) currents in single rat or mouse mVSM cells and diameter responses of isolated arterioles in conjunction with adenoviral methods to manipulate the expression of selected proteins in arteriolar smooth muscle. There are two specific aims Aim A will focus on how longitudinal cell stretch is transduced through integrins to potentiate CBL and BK channels and myogenic tone. We predict that: aSpi integrin but not avp3 integrin transduces mechanical force to regulate CBL and BK channels; talin-1, paxillin, a-actinin and p130Cas are critical focal adhesion proteins required for force transmission through integrins to VSM channels; stretch-induced potentiation of by integrin-linked kinases and phosphatases. Aim B will focus on how avpS integrin functions as a matricryptin receptor to inhibit myogenic tone. We predict that: fibronectin, osteopontin and collagen contain matricryptic sites that induce arteriolar dilatation; matricryptins act by inhibition of mVSM CaL channels and/or activation of BK channels; matricryptin-induced signaling through avpS integrin is mediated by phosphorylation of the p3 integrin tail by Src. The studies will expand our knowledge of how physiologic stretch regulates key VSM ion channels and how proteolytic fragments of ECM proteins exert their vasoactive effects.

血管整合素和血管壁ECM成分之间的相互作用是重要的 小动脉张力和血流控制的决定因素。在项目2中，我们关注ECM-整合素相互作用急性调节血管张力的血管功能的两个方面：1）通过电压门控L型Ca^* 通道（CBL）和BK（大电导钙激活K*）通道的血管内压力的机械转导，以及2）生物活性基质隐蛋白（即，具有血管活性特性的ECM蛋白的蛋白水解片段）。项目2的中心假设是α 5 β 1介导生理牵张传导至mVSM离子通道以增强血管紧张性，而α v β 3介导作为基质蛋白受体以抑制血管紧张性并启动血管舒张以响应血管壁损伤。将使用膜片钳方法记录单个大鼠或小鼠mVSM细胞中的CaL和BK（大电导钙激活K* 通道）电流以及分离的小动脉的直径反应，结合腺病毒方法来操纵小动脉平滑肌中选定蛋白质的表达，从而对该假设进行检验。有两个具体的目标，目标A将集中在纵向细胞拉伸是如何通过整合素转导，以加强CBL和BK通道和肌源性紧张。我们预测：α Spi整联蛋白而不是α ν β 3整联蛋白转导机械力以调节CBL和BK通道; talin-1、桩蛋白、α-辅肌动蛋白和p130 Cas是通过整联蛋白向VSM通道传递力所需的关键粘着斑蛋白;牵张诱导的整联蛋白连接的激酶和磷酸酶的增强作用。目的B将关注avpS整合素如何作为基质密码蛋白受体抑制肌源性张力。我们预测：纤连蛋白、骨桥蛋白和胶原蛋白含有诱导小动脉扩张的基质密合位点;基质密合蛋白通过抑制mVSM CaL通道和/或激活BK通道起作用;基质密合蛋白诱导的通过α v β S整联蛋白的信号传导由Src对β 3整联蛋白尾部的磷酸化介导。这些研究将扩大我们对生理牵张如何调节关键VSM离子通道以及ECM蛋白的蛋白水解片段如何发挥其血管活性作用的认识。