MOLECULAR ANALYSIS OF SEROTONIN RECEPTOR FUNCTION

这里提出的工作的总体目标是了解如何 神经递质通过以下方式调节细胞和生理过程 与特定的细胞表面受体相互作用。重点将放在 5-羟色胺[5-羟色胺，5HT]，一种生物胺，参与 中枢和外周的一系列生理反应 神经系统。5-羟色胺通过与一种 结构和功能相关的细胞表面受体家族， 每一种都有不同的药理特性。此外，这些 亚型与不同的细胞内第二信使信号耦合 小路。在大脑中，5-羟色胺受体被认为起着关键作用。 在调节情感和知觉状态方面，和是 大量的精神药物，包括LSD。在脊髓中，5-羟色胺 参与疼痛的中枢调节，而在外周 5-羟色胺调节肠道反射和平滑肌收缩。 因此，这些受体是药物的潜在靶点。 情感障碍的治疗(强迫行为、抑郁 和精神分裂症)，偏头痛和疼痛。 编码三种5HT受体亚型(5HT1a、5HT1c和5HT2)的基因现在 被克隆，从而允许对受体结构和 功能。当在成纤维细胞的非自然环境中表达时， 5HT1c和5HT2受体亚型结合配体并激活细胞内 第二信使信号系统。这项建议的第一个目的是 通过分离扩大5-羟色胺受体亚型的分子特征 使用标准重组DNA的该基因家族的其他成员 方法论。第二个目标是利用成纤维细胞表达 系统作为识别这些受体突变的一种手段 它们的配体结合或信号转导特性。第三个目标是 细胞内第二信使信号的生化特征 这些受体在成纤维细胞和神经母细胞瘤中的偶联途径 培养中的细胞。使用这些简单的体外系统作为模型，它应该 有可能进一步了解这些受体如何在体内发挥作用 神经元。

The overall objective of the work proposed here is to understand how neurotransmitters modulate cellular and physiological processes by interacting with specific cell surface receptors. The focus will be on serotonin [5-hydroxytryptamine, 5HT], a biogenic amine that is involved in a wide array of physiological responses in the central and peripheral nervous system. Serotonin exerts its physiological effects by binding to a family of structurally- and functionally-related cell surface receptors, each having distinct pharmacological properties. In addition, these subtypes couple to different intracellular second messenger signaling pathways. In the brain, serotonin receptors are believed to play a key role in modulating affective and perceptual states, and are sites of action of numerous psychotropic drugs, including LSD. In the spinal cord, serotonin is involved in the central regulation of pain, while in the periphery serotonin modulates enteric reflexes and the contraction of smooth muscle. As such, these receptors are potential targets for the pharmaceutical treatment of affective disorders (obsessive-compulsive behavior, depression and schizophrenia), migraine headaches and pain. Genes encoding three 5HT receptor subtypes (5HT1a, 5HT1c and 5HT2) have now been cloned, permitting a molecular analysis of receptor structure and function. When expressed in the unnatural environment of a fibroblasts, the 5HT1c and 5HT2 receptor subtypes bind ligands and activate intracellular second messenger signaling systems. The first aim of this proposal is to extend the molecular characterization of 5HT receptor subtypes by isolating other members of this gene family using standard recombinant DNA methodologies. The second objective is to use the fibroblast expression system as a means for identifying mutations in these receptors that alter their ligand binding or signal transduction properties. The third aim is to biochemically characterize the intracellular second messenger signaling pathways to which these receptors couple in fibroblasts and neuroblastoma cells in culture. Using these simple in vitro systems as models, it should be possible to further our understanding of how these receptors operate in neurons.