RECEPTOR SIGNALING IN POLYPLOID VASCULAR SMOOTH MUSCLE

拟议的研究计划集中在离子、生物化学和细胞方面。 血管收缩激动剂(血管紧张素II、Kc1)与生长的机制 因子(血小板衍生生长因子)对二倍体和多倍体的作用 血管平滑肌细胞(VSMC)分离自不同血管 (动脉、尾动脉和肠系膜动脉)血压正常，自发性 高血压大鼠和DOCA/盐性高血压大鼠。新隔离的，以及 培养的VSMC将用于这些研究。详细分析了 细胞内钙和pH将使用流式细胞仪和新的 发展了与荧光比率相关的多参数分析方法 成像显微镜。具体目标包括：1)提供详细的 静息细胞内钙和pH的逐个细胞分析 流式细胞仪检测二倍体/四倍体VSMC的膜电位。在……里面 此外，空间和区域分布的差异(核与 细胞内的钙和pH将被评估；2)测定 二倍体/多倍体(四倍体、八倍体)VSMC是否来自高血压 与正常动物相比，动物的信号转导途径发生了变化 二倍体VSMC。我们还将比较和对比地区差异 血管紧张素II和PDGF刺激后细胞内钙离子和pH的变化； 3)评估细胞-细胞相互作用的生理相关性 VSMC的二倍体和多倍体群体；4)细胞遗传学检查 促进多倍体VSMC发育的机制 表型。这些研究应该有助于我们对 VSMC反应正常和改变的机制与 高血压、动脉粥样硬化和动脉血管痉挛的发病机制。

The proposed research program focuses on ionic, biochemical and cellular mechanisms of vasoconstrictor agonist (angiotensin II, KC1) and growth factor (platelet-derived growth factor) action on diploid and polyploid vascular smooth muscle cells (VSMC) isolated from different blood vessels (aorta, caudal artery and mesenteric artery) of normotensive, spontaneously hypertensive and DOCA/salt hypertensive rats. Freshly isolated, as well as cultured VSMC will be used in these studies. A detailed analysis of cytosolic calcium and pH will be made using flow cytometry and newly developed multiparameter analytical methods related to fluorescence-ratio imaging microscopy. The specific aims include: 1) providing a detailed cell-by-cell analysis of resting cytosolic calcium and pH, as well as membrane potential, in diploid/tetraploid VSMC via flow cytometry. In addition, differences in the spatial and regional distribution (nuclear vs. cytosolic) of cellular calcium and pH will be assessed; 2) determining whether diploid/polyploid (tetraploid, octaploid) VSMC from hypertensive animals possess altered signal transduction pathways as compared to normal diploid VSMC. We will also compare and contrast the regional differences in cytosolic calcium and pH following angiotensin II and PDGF stimulation; 3) evaluating the physiological relevance of cell-cell interactions between diploid and polyploid populations of VSMC; and 4) examining the cytogenetic mechanisms which contribute to the development of the polyploid VSMC phenotype. These studies should contribute to our basic understanding of the mechanisms of normal and altered VSMC responsiveness related to the pathogenesis of hypertension, atherosclerosis and arterial vasospasm.