PURINERGIC AXIS OF CARDIAC BLOOD VESSELS

这项拟议的研究的目标是解释 胞外腺嘌呤核苷酸，特别是腺苷5‘- 三磷酸(ATP)，在正常的心脏内皮细胞(EC)功能 参与血液调节的因子的释放 血流在正常心功能和心血管疾病中可能很重要。 疾病。血管内皮细胞已被证明可以释放三磷酸腺苷和类金丝桃酸，如 内皮依赖性松弛因子和前列环素对血管紧张素转换酶的影响 各种刺激，包括三磷酸腺苷本身。此外，我们建议欧洲共同体 能在细胞外将腺苷5‘-二磷酸(ADP)转化为ATP，从而 维持三磷酸腺苷介导的冠脉和冠脉的松弛 阻力血管从ATP释放部位顺流而下。我们建议 对ATP出现在欧共体之外的控制及其最终 转化为腺苷是局部血液的重要组成部分 正常心脏的血流控制。由于尚不清楚三磷酸腺苷是如何释放的 或由ECS将ADP转换为ATP受到监管，具体目标有 设计如下： 1.检验这样一种假设，即内皮细胞释放的ATP和 血管内皮细胞将ADP转化为ATP可以在完整的冠状动脉中测量 动脉和ATP释放可以支持核苷三磷酸 队形。此外，为了检验ADP转化率的假设 对ATP的原位抑制作用及判断缺氧对其的影响 细胞外产生的ATP。 2.检验心脏内皮细胞释放三磷酸腺苷 激动剂在发光和发光两种情况下都会出现，并测试 缺氧和复氧对这一过程的影响。 3.探索ECs释放ATP的方式并检验假设 受刺激的内皮细胞对三磷酸腺苷的精加工是相关的， 从机制上讲，与内皮细胞释放一氧化氮的能力有关。 4.评估胞外核苷二磷酸激酶和胞外核苷二磷酸的作用。 腺苷酸激酶在内皮细胞胞外产生三磷酸腺苷中的作用及检测 低氧和复氧对这些酶活性的影响。 我们将通过生物化学、药理学、 使用完整的分子、细胞生物学和显微方法 血管、原代培养的细胞和亚细胞组分。

The goal of the proposed research is to explain the role of extracellular adenine nucleotides, particularly adenosine 5'- triphosphate (ATP), in normal cardiac endothelial cell (EC) function where release of factors that participate in the regulation of blood flow may be important in normal cardiac function and in cardiovascular disease. ECs have been shown to release ATP and autacoids such as endothelium-dependent relaxing factor and prostacyclin in response to various stimuli, including ATP itself. In addition, we propose that ECs can convert adenosine 5'-diphosphate (ADP) to ATP extracellularly to maintain the presence of ATP-mediated relaxation of the coronary and resistance vessels down-stream from the site of ATP release. We suggest that control of ATP appearance outside the EC and its eventual conversion to adenosine is an important component of regional blood flow control in the normal heart. As it is not clear how release of ATP or conversion of ADP to ATP by ECs is regulated, specific aims have been designed as follows: 1. Test the hypothesis that the release of ATP from ECs and the conversion of ADP to ATP by ECs can be measured in an intact coronary artery and that ATP release can support nucleoside triphosphate formation. Furthermore, to test the hypothesis that conversion of ADP to ATP can be inhibited in situ and determine the affect of hypoxia on extracellular generation of ATP. 2. Test the hypothesis that cardiac EC release of ATP in response to agonists occurs both luminally and abluminally and test the effect of hypoxia and re-oxygenation on this process. 3. Explore the manner in which ECs release ATP and test the hypothesis that the elaboration of ATP by stimulated ECs is associated, mechanistically, with the ability of ECs to release nitric oxide. 4. Assess the role of ecto-nucleoside diphosphate kinase and ecto- adenylate kinase in the extracellular production of ATP by ECs and test effects of hypoxia and reoxygenation on the activity of these enzymes. We will approach these aims with biochemical, pharmacological, molecular, cell biological and microscopic methods employing intact blood vessels, cells in primary culture and subcellular fractions.