ANESTHETIC ACTION ON NEUROTRANSMITTER RESPONSES

对神经递质反应的麻醉作用

• 批准号: 7384098
• 负责人: Joseph H. Steinbach
• 金额: $ 34.95万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7384098
• 关键词: Aminobutyric Acid; Aminobutyric Acids; Anesthesia procedures; Anesthetics; Binding; Binding Sites; Biochemical; Cell Line; Cell membrane; Cells; Chemosensitization; Class; Epitopes; Funding; GABA-A Receptor; Gated Ion Channel; General anesthetic drugs; Glycine; Goals; Kinetics; Lead; Location; Mediating; Membrane; Molecular; Mutate; Mutation; Nature; Neurons; Neurotransmitters; Pharmaceutical Preparations; Physiological; Population; Recombinants; Research; Research Design; Role; Shapes; Site; Specificity; Steroid Receptors; Steroids; Structure; Surface; Transfection; Work; analog; base; gamma-Aminobutyric Acid; insight; novel; programs; receptor; research study; response; steroid analog

PROJECT 3 This Project will study the actions of steroid anesthetics on transmitter-gated ion channels. The focus is on potentiation of responses of the GABA-A receptor by steroids, as potentiation is most clearly related to anesthetic actions. A central goal of the work is to define the structural requirements for specific steroid effects. Work in the present funding period has shown that steroids have 3 distinct kinetic effects on the GABA-A receptor, and that the effects are mediated by binding to at least 2 sites. We will use biophysical analyses of evoked currents to determine the structures of the steroid molecule which are required for these effects, in complementary experiments, we will study the consequences of mutations to proposed steroid binding regions in the GABA-A receptor. We will also perform experiments to identify the location of the steroid binding pocket in the receptor with respect to the cell membrane, that is, whether it is located in the inner or outer leaflet of the membrane. In studies performed during the present funding period, we have found that the effects of steroids depend on the concentration of transmitter (GABA) used to activate the receptor, which may have a significant role in shaping the physiological actions of steroids. We will study the basis for the this relationship. We will continue to produce recombinant epitope tagged GABA-A receptors, for use in biochemical studies. Finally, we will determine the effects of steroids on the function of additional receptors, including the glycine a3 receptor. The proposed work builds on previous results from this Project and the Program as a whole. It is expected to lead to significant insights into the nature and location of the steroid binding sites on the GABA- A receptor. Further, it is expected to reveal the critical molecular mechanisms by which steroid anesthetics produce functional effects associated with anesthesia. Finally, it should assist in developing insights into the parts of the steroid molecule which are associated with specific functional consequences, which could result in increased specificity or efficacy for steroid anesthetics.

项目3 本计画将研究类固醇麻醉药对离子通道的作用。重点是 类固醇增强GABA-A受体的反应，因为增强作用最明显地与 麻醉作用这项工作的中心目标是确定特定类固醇的结构要求 方面的影响.在目前的资助期内的工作表明，类固醇有3个不同的动力学效应， GABA-A受体，并且通过与至少2个位点结合介导作用。我们将使用生物物理学 分析诱发电流以确定这些所需的类固醇分子的结构， 影响，在补充实验中，我们将研究拟议类固醇突变的后果 GABA-A受体中的结合区。我们还将进行实验，以确定 受体中相对于细胞膜的类固醇结合口袋，即它是否位于细胞膜中 膜的内部或外部小叶。在本资助期内进行的研究中，我们 发现类固醇的作用取决于用于激活神经元的递质（GABA）的浓度。 受体，这可能在塑造类固醇的生理作用中发挥重要作用。我们会研究 这种关系的基础。我们将继续生产重组表位标记的GABA-A受体， 用于生物化学研究。最后，我们将确定类固醇对额外的功能的影响。 受体，包括甘氨酸A3受体。 拟议的工作建立在该项目和整个计划的先前成果的基础上。是 预期将导致显着的见解的性质和位置的类固醇结合位点的GABA- 一种受体。此外，它有望揭示类固醇麻醉剂的关键分子机制， 产生与麻醉相关的功能效应。最后，它应有助于深入了解 类固醇分子的某些部分与特定的功能后果有关，这可能导致 增加类固醇麻醉剂的特异性或有效性。