CORONARY ANGIOGENESIS-VASCULOGENESIS REGULATION

冠状动脉血管生成-血管生成调节

• 批准号: 2225072
• 负责人: ROBERT J TOMANEK
• 金额: $ 16.89万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-05-25 至 1996-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2225072
• 关键词: angiogenesis; cell migration; chick embryo; collagen; coronary artery; coronary vessels; electron microscopy; embryogenesis; extracellular; fibroblast growth factor; fibronectins; heart ventricle; hemodynamics; histochemistry /cytochemistry; histogenesis; immunocytochemistry; in situ hybridization; laboratory rat; messenger RNA; morphology; species difference

The overall goal of this project is to elucidate the events, patterns and factors regulating coronary angiogenesis. We will utilize electron microscopy, morphometry, histochemistry, immunocytochemistry, in situ hybridization, and hemodynamic assessment to study prenatal rat and in ovo chick hearts. The first aim is to define the transmural and regional vascularization patterns in the ventricles of these species. The second aim is to establish the formation of the major coronary arteries. Since the extracellular matrix (ECM) modulates endothelial cell migration and tube formation, Aim 3 is to determine the role of selective ECM molecules in the regulation of coronary angiogenesis. Our underlying hypothesis is that key components of the ECM, i.e., laminin, fibronectin, and collagens I, III, and IV, are critical to the formation of coronary vessels. Our fourth aim is to test the hypothesis that fibroblast growth factors are essential in vivo regulators of coronary angiogenesis. Studies in Aims 3 and 4 will be based on avascular fetal rat hearts implanted in oculo where they become vascularized, innervated and beat spontaneously. To test these hypotheses we will introduce blocking agents for the extracellular molecules and growth factors in oculo along with the implant, and study implant vascularization at various time points. Localization of selected key ECM molecule mRNAs will be performed by in situ hybridization in order to establish whether their synthesis corresponds to sites of angiogenesis. In additional experiments we will document the effects of the blocking agents on endothelial cell migration and tube formation by utilizing avascular fetal rat hearts cultured in vitro. Aims 5 and 6 will test the hypotheses that the early growth of the coronary vasculature is dependent upon hemodynamic load and cardiac mass. In chick hearts in ovo we will increase hemodynamic load and myocyte hyperplasia by constricting the outflow tract. In contrast, a decreased hemodynamic load and a decreased cardiac mass associated with hypoplasia of cardiocytes will be accomplished by chronic verapamil suffusion. These conditions will be imposed prior to vascularization, and the data compared to hearts not subjected to perturbations (Aim 1). Our studies are of particular significance because 1) there is a paucity of data on coronary angiogenesis, and 2) our novel models and approaches provide the opportunity to examine the role of key intrinsic and extrinsic factors in the regulation of coronary angiogenesis in vivo.

该项目的总体目标是阐明事件，模式和 调节冠状动脉生成的因素。 我们将利用电子 显微镜，形态计量学，组织化学，免疫细胞化学，原位 杂交和血液动力学评估，以研究产前大鼠和 Ovo Chick Hearts。 第一个目的是定义透壁和区域 这些物种的心室中的血管化模式。 第二个 目的是建立主要冠状动脉的形成。 自从 细胞外基质（ECM）调节内皮细胞迁移和 Tube形成，目标3是确定选择性ECM分子的作用 在冠状动脉生成的调节中。 我们的基本假设 是ECM的关键成分，即层粘连蛋白，纤连蛋白和 胶原I，III和IV对冠状动脉的形成至关重要 船只。 我们的第四个目标是检验成纤维细胞生长的假设 因素在冠状动脉生成的体内调节剂中至关重要。 目标3和4的研究将基于血管胎儿大鼠心脏 植入Oculo，在那里它们变得血管化，神经支配和殴打 自发。 为了检验这些假设，我们将引入阻止 Oculo中细胞外分子和生长因子的药物沿 与植入物和研究植入物血管化的不同时间 点。 选定的ECM分子mRNA的定位将是 通过原位杂交进行的，以确定其是否是否 合成对应于血管生成部位。 附加 实验我们将记录阻塞剂对 内皮细胞迁移和试管形成 胎儿大鼠心脏在体外培养。 目标5和6将测试 假设冠状动脉血管的早期生长取决于 血流动力学负荷和心脏质量。 在小鸡的心中，我们将 通过收缩来增加血液动力学负荷和心肌细胞增生 流出道。 相反，血液动力学负荷减少和减少 与心脏不足有关的心脏肿块将是 通过慢性维拉帕米的充足来完成。 这些条件将是 在血管形成之前强加了，与心脏相比的数据不是 受到扰动（目标1）。 我们的研究特别 意义是因为1）关于冠状动脉的数据很少 血管生成，2）我们的新型模型和方法提供了 检查关键内在和外在因素的作用的机会 在体内冠状动脉生成的调节中。