PDE1C REGULATION OF VASCULAR SMOOTH MUSCLE PROLIFERATION

描述：动脉平滑肌细胞（SMC）通常在一个 收缩的非增殖状态 动脉损伤可导致SMC 经历活化进入增殖状态。 cAMP和cGMP抑制 增殖和SMC不断暴露于升高这些 因此，cAMP和cGMP的降解增强是必要的。 研究人员假设，在人类SMC中， 磷酸二酯酶（PDE1C）必须被诱导以降解环核苷酸。 本申请的重点是确定PDE1C在SMC中的作用 增殖 研究人员建议在四个特定的领域进行研究。 目标。 目的1提出了PDE1C是否仅限于增殖SMC的问题。 潜在的假设是PDE1C将高表达于 增殖，合成SMC在体外和在正常和疾病过程中 其特征在于增加的SMC增殖（动脉粥样硬化病变， 新生儿肺动脉高压，球囊血管成形术） 组织. 相反，静止细胞应该表达很少的PDE1C。 目的2解决了细胞外基质的潜在重要性， PDE1C表达的调控。 动脉病变可能使SMC暴露于各种 细胞外基质的成分，初步研究表明， 单体胶原可以上调PDE1C，而纤维胶原则不能 有这种效果。 为此，研究人员将研究 细胞外基质的各种成分对PDE1C表达的影响。 他们 还将确定p70 S6激酶途径的作用， 受细胞外基质的调节。 目的3将描述PDE1C启动子中的哪些区域赋予敏感性 细胞外基质和细胞内信号诱导这些 矩阵 人平滑肌细胞PDE1C及其启动子区的克隆和鉴定 与报告构建体偶联的截短启动子序列的产生 将提供关于调节PDE1C表达的序列的信息。 目标4将询问SMC是否需要PDE1C 增殖 将使用药理学抑制剂抑制PDE1C， 以及该酶的反义mRNA。 SMC表型变化 将确定过表达PDE1C的细胞中的增殖状态。 相反，PDE1C的抑制剂应该防止SMC增殖。

DESCRIPTION: Arterial smooth muscle cells (SMC) are ordinarily in a contractile, nonproliferative state. Arterial injury can cause SMC to undergo an activation into a proliferative state. cAMP and cGMP inhibit proliferation and SMC are constantly exposed to agents elevating these mediators, therefore enhanced degradation of cAMP and cGMP are necessary. The investigators have hypothesized that in human SMC, a new phosphodiesterase (PDE1C) must be induced to degrade cyclic nucleotides. This application focuses on determination of the role of PDE1C in SMC proliferation. The investigators propose to study this in four specific aims. Aim 1 asks the question whether PDE1C is restricted to proliferating SMC. The underlying hypothesis is that PDE1C will be highly expressed in proliferating, synthetic SMC in vitro and in normal and disease processes characterized by increased SMC proliferation (atherosclerotic lesions, neonatal pulmonary hypertension, balloon angioplasty) in human or ovine tissue. Conversely, quiescent cells should express little PDE1C. Aim 2 addresses the potential importance of the extracellular matrix in regulation of PDE1C expression. Arterial lesions may expose SMC to various components of the extracellular matrix and preliminary studies suggest monomer collagen can upregulate PDE1C, while fibrillar collagen does not have this effect. In this aim, the investigators will study the effect of various components of the extracellular matrix on PDE1C expression. They will also determine the role of the p70 S6 kinase pathway which is known to be regulated by extracellular matrix. Aim 3 will delineate what regions in the PDE1C promoter confer sensitivity to extracellular matrices and intracellular signals induced by these matrices. Cloning of the human SMC PDE1C and its promoter region and generation of truncated promoter sequences coupled to reporter constructs will provide information about sequences regulating PDE1C expression. Aim 4 will ask the question of whether PDE1C is required for SMC proliferation. PDE1C will be inhibited using pharmacologic inhibitors as well as antisense mRNA of the enzyme. Change in SMC phenotype to the proliferative state in cells overexpressing PDE1C will be determined. Inhibitors of PDE1C should conversely, prevent SMC proliferation.