DEVELOPMENT AND MODULATION OF PRESYNAPTIC ION CHANNELS

该提案要求为我所在的研究项目提供工资支持 发展中的。因此，它侧重于两个相关但具体的领域 实验室两年来开展的研究工作：(1) 突触前离子通道的发展及其在胆碱能中的作用 体外静脉曲张，以及(2)生长抑素对神经元的调节 钙离子通道。两者都是我长期目标中不可或缺的一部分 制定强有力的研究计划，在发展、监管和 神经元突触前功能的调节。 第一个具体目标集中在突触前离子的发展上 通道及其在胆碱能静脉曲张中的作用。这些 实验是为了研究突触前的诱导 特化(钙和钙激活的钾通道)表达于 在培养中沿神经突起形成的递质释放曲张 非洲爪哇的脊髓神经元和肌细胞。使用膜片钳 技术，我建议(1)直接描述电流的类型 存在于新形成的突触前结构，(2)确定它们的作用 在递质释放调节中，以及(3)识别细胞-细胞 调节这些专门化表达的相互作用。从… 这些研究应该对运动神经有更深入的了解。 终末钙和钙激活的钾通道，它们在 递质释放和突触前特化的诱导。 第二个具体目标集中在调制机制上。 副交感神经元上的钙通道。生长抑素对血管紧张素转换酶的影响 将研究睫状神经节神经元的钙电流，作为 发生在脉络膜神经末梢的调制。这是非常困难的。 为了直接研究突触前离子电流在脑内的调制 准备工作。这在很大程度上是由于规模较小， 发射器释放区域无法进入。严重割裂 将睫状神经节神经元作为体外培养的模型，并利用 膜片钳技术，我建议阐明信号转导 偶联生长抑素受体抑制钙离子的级联反应 频道。拟议中的实验将提供有价值的见解 钙通道的调控机制。 独立科学家奖(NINDS-RCDA)将提供 在不占用我大量时间的情况下追求这些研究目标 教学和行政职责。威斯康星大学神经科学系 匹兹堡大学是一个理想的环境，在那里我可以 促进和借鉴科学交流的氛围。那里 这个系里有很多研究人员从事研究解决 突触生理学的某些方面(LTP、NMDA受体研究、运动 突触的控制、离子通道调节和生化研究 传输)。从很多方面来说，这是我成长的理想环境 专业，并在突触方面开发强大的研究计划 生理学。

The proposal requests salary support for the research program that I am developing. As such, it is focused on two related, but specific areas of research developed in the laboratory over the past two years: (1) development of presynaptic ion channels and their role at cholinergic varicosities in vitro, and (2) somatostatin modulation of neuronal calcium (Ca++ ) channels. Both are integral parts in my long-term goal to develop a strong research program in the development, regulation, and modulation of neuronal presynaptic function. The first specific aim is focused on the development of presynaptic ion channels and their role at cholinergic varicosities in vitro. These experiments are designed to study the induction of presynaptic specialization (Ca++ and calcium-activated K+ channels) expressed at transmitter-releasing varicosities that form along neurites in cultures of Xenopus spinal cord neurons and myocytes. Using patch clamp techniques, I propose to (1) characterize directly the types of currents present at newly formed presynaptic structures, (2) determine their role in transmitter release regulation, and (3) identify cell-cell interactions that regulate the expression of these specializations. From these studies should come a more thorough understanding of motor nerve terminal Ca++ and calcium-activated K+ channels, their role in transmitter release and the induction of presynaptic specialization. The second specific aim is focused on the mechanisms of modulation of Ca++ channels in parasympathetic neurons. The effects of somatostatin on Ca++ currents will be studied in ciliary ganglion neurons as a model for modulation that occurs at choroid nerve terminals. It is very difficult to study directly the modulation of presynaptic ionic currents in this preparation. This is due, in large part, to the small size and inaccessibility of the transmitter releasing regions. Acutely dissociated ciliary ganglion neurons will be used in vitro as a model, and using patch clamp techniques, I propose to elucidate the signal transduction cascade that couples somatostatin receptors to inhibition of Ca++ channels. The proposed experiments will provide valuable insights into the mechanisms of modulation of Ca++ channels. The Independent Scientist Award (NINDS - RCDA) would provide the freedom to pursue these research goals without large demands on my time for teaching and administrative duties. The Department of Neuroscience at the University of Pittsburgh is an ideal environment in which I can both contribute to, and draw from, an atmosphere of scientific exchange. There are many researchers in this department engaged in research addressing some aspect of synaptic physiology (LTP, NMDA receptor studies, motor control, ion channel regulation, and biochemical studies of synaptic transmission). In many ways, this is an ideal environment for me to grow professionally, and develop a strong research program in synaptic physiology.