CHEMICAL TRANSMISSION IN SENSORY RECEPTORS

感觉受体被归类为“初级”受体(其中感觉 End是由刺激直接兴奋)或‘次级’受体(其中 感官刺激的传递需要一个前神经细胞)。 因此，次级受体需要两个受体之间的电或化学耦合 前神经细胞和传入神经纤维。颈动脉小体 化学感受器被认为是第二类受体，与化学物质 感觉突触被认为存在于神经前(I型)细胞和 颈动脉窦神经的感觉终末。推定 神经递质，包括生物胺(儿茶酚胺和 乙酰胆碱)和神经活性多肽(脑啡肽和P物质 包含在该受体中，并被认为在高血压的发生中起作用 化学反应。这项提案的目标源于我们的 并继续围绕一个中心目标进行研究：即 阐明感觉传递和化学转导的机制 颈动脉小体。以下五个项目是为新的 授权期：生物胺的作用研究(项目1)和 神经肽(项目2)将描述两者之间的关系 化学感觉放电，合成(和/或含量)，释放，和 这些物质的受体作用部位。重点将放在 共递质相互作用与感觉调节的研究 Synapse。神经肽和酶的分布与共存 生物胺合成(项目3)将使用一套新的 颗粒标记与分析电子显微镜相结合 (AEM)。关于刺激传导机制的研究(项目4)将 探讨能量代谢(2DG、ATP测定)和离子触发事件 (CA++条目)与化学反应相关联。最后，我们对 次级感官受体的营养现象(项目5)将继续 通过再神经支配实验来评估逆行营养 感觉末梢器官对递质特异性表达的影响 成熟感觉神经元的特征。 这项多学科研究涉及的实验需要多种多样。 方法和技术，包括：发射机的高效液相色谱和放射免疫分析 物质，发射器储存和释放的无线电标记，接收器 结合、酶分析、放射自显影、免疫细胞化学(光镜和免疫细胞化学)、 电生理技术，2-DG-P和ATP测量，以及LM和EM 营养现象的评估。

Sensory receptors are categorized as 'primary' receptors (where the sensory ending is excited directly by the stimulus) or 'secondary' receptors (where the transduction of the sensory stimulus requires a pre-neural cell). Secondary receptors thus require electrical or chemical coupling between pre-neural cells and afferent nerve fibers. The carotid body chemoreceptors are considered secondary-type receptors, with chemical sensory synapses thought to exist between pre-neural (type I) cells and sensory terminations of the carotid sinus nerve. Putative neurotransmitters, including biogenic amines (catecholamines and acetylcholine) and neuroactive peptides (enkephalins and substance P) are contained in this receptor and are thought to play a role in the genesis of the chemoresponse. The objectives of this proposal proceed from our previous studies and continue to pivot about a central goal: i.e., to elucidate the mechanisms of sensory transmission and chemotransduction in the carotid body. The following five projects are proposed for the new grant period: Studies on the role of biogenic amines (Project 1) and neuropeptides (Project 2) will characterize the relationship between chemosensory discharge, and synthesis (and/or content), release, and receptor sites of action for these substances. Emphasis will be on studies of co-transmitter interactions and modulation of the sensory synapse. The distribution and co-existence of neuropeptides and enzymes of biogenic amine synthesis (Project 3) will be examined using a novel set of particulate markers in combination with analytical electron microscopy (AEM). Studies on the mechanisms of stimulus transduction (Project 4) will explore the energetic metabolism (2DG, ATP assays) and ionic trigger events (Ca++ entry) associated with the chemoresponse. Finally, our studies of trophic phenomena in secondary sensory receptors (Project 5) will continue with re-innervation experiments which assess the retrograde trophic influence of sensory end-organs on the expression of transmitter specific characteristics in mature sensory neurons. The experiments involved in this multi-disciplinary study require a variety of methods and techniques, including: HPLC and RIA of transmitter substances, radio-labelling of transmitter stores and release, receptor binding, enzyme assays, auto-radiography, immunocytochemistry (LM and AEM), electrophysiological techniques, 2-DG-P and ATP measurements, and LM and EM assessment of trophic phenomena.