ENDOTHELIAL DEPENDENCE OF MICROCIRCULATORY REGULATION

拟议的工作是基于项目负责人之前的研究 与本计划项目的联系和已得到的初步数据 获得了血管活性、内皮衍生介质在 微血管功能的调节。 我们计划继续检查 内皮源性一氧化氮、前列腺素的具体作用 和氧自由基种类在血管反应性以及剪切力中的作用 应激和压力引起的体内和体内微血管张力的变化 体外。 在具体目标 1 的背景下，我们将检验以下假设： 参与传递的信号转导途径 通过微血管内皮细胞的剪切力导致 一氧化氮和前列腺素的释放与酪氨酸激酶有关 内皮细胞的活性、细胞骨架结构和钾通道 细胞。 我们还计划研究 ecNOS 诱导的时间过程 微血管响应剪切应力增加的活动。 在 具体目标 2 我们将继续研究运动的效果 大鼠微血管内皮细胞功能训练。 我们将测试 血流量间歇性增加（剪切应力）的假设 在运动期间会导致上调 ecNOS、COX-1 和 SOD，以及一氧化氮可用性的增加 会影响骨骼肌的氧代谢，所有这些都会倾向于 促进运动训练者的血液流动和工作效率的增加 骨骼肌。 在具体目标 3 中，内皮细胞对 将调查心力衰竭引起的动脉功能变化 在狗的冠状动脉和骨骼肌血管以及冠状微血管中 人类的。 我们将检验心力衰竭与此相关的假设 内皮合成/和/或活性严重降低 一氧化氮和扩张前列腺素的微血管，这 缺陷会导致循环衰竭。 在所有三个目标中的回应 对于激动剂，流量和压力将在隔离、灌注中进行研究 在受控条件下以及在体内的某些情况下，通过 既定方法，包括电视直径测量 显微镜。 血管灌注液中的一氧化氮将被检测为 NO(2)， 在血浆中为 NO(3)； cNOS、COX-1 和 SOD 基因表达和酶 水平将通过分子生物学技术进行量化 免疫组织化学。

The work proposed is based on the Project Leader's previous studies in connection with this Program Project and preliminary data that have been obtained on the role of vasoactive, endothelium-derived mediators in the regulation of microvascular function. We plan to continue the examination of the specific roles of endothelium-derived nitric oxide, prostaglandins and oxygen radical species in vascular reactivity, as well as in shear stress and pressure-induced changes in microvascular tone, in vivo and in vitro. In the context of Specific Aim 1 we will test the hypothesis that the signal transduction pathway that is involved in the transmission of shear forces through microvascular endothelial cells to result in the release of nitric oxide and prostaglandins is related to tyrosine kinase activity, cytoskeletal structures and potassium channels in endothelial cells. We also plan to study the time course of the induction of ecNOS activity in microvessels in response to increases in shear stress. In Specific Aim 2 we will continue our studies of the effects of exercise training on microvascular endothelial cell function in rats. We will test the hypothesis that intermittent increases in blood flow (shear stress) during episodes of exercise activity will result in the upregulation of ecNOS, COX-1 and SOD, and that the increased availability of nitric oxide will affect skeletal muscle oxygen metabolism, all of which will tend to promote increases in blood flow in and work efficiency of exercise-trained skeletal muscle. In Specific Aim 3 the endothelial contribution to changes in arteriolar function due to heart failure will be investigated in coronary and skeletal muscle vessels of dogs and coronary microvessels of humans. We will test the hypothesis that heart failure is associated with a severe reduction in the endothelial synthesis/and or activity in microvessels of both nitric oxide and dilator prostaglandins and that this defect contributes to circulatory collapse. In all three aims responses to agonists, flow and pressure will be studied in isolated, perfused arterioles under controlled conditions and in some instances in vivo, by established methods, including diameter measurements by television microscopy. Nitric oxide will be assayed in vessel perfusates as NO(2), and in plasma as NO(3); cNOS, COX-1 and SOD gene expression and enzyme levels will be quantified by molecular biology techniques and immunohistochemistry.