NEUROTRANSMITTERS AND VISCERAL SENSORY NEURONS

迷走神经的内脏感觉神经元支配主要器官 胸部和腹部的系统。迷走感觉神经元传递 关于各种刺激的信息，如血压、胃 终末扩张、细支气管炎和血氧 在脑干的孤束核(NTS)。然而，很多都是 已知的感觉受体，神经解剖通路 传入神经元及其反射，神经递质包含 在迷走神经中，感觉神经的特征不是很好。我们建议研究 与这些神经元相关的神经递质系统(S)。我们的 初步工作表明，推测的神经递质的存在 迷走神经传入神经元中的P物质(SP) 化学感受性传入纤维)，并在NTS内显示SP受体。其他 有证据表明，CCK和5-羟色胺(5-羟色胺)是潜在的 迷走神经感觉神经元中的递质。因此，我们将同时 研究这3个发射机系统(1)以确定主源的位置 NTS中的药物对周围或中枢神经元的影响，(2)研究 迷走神经感觉胞体内递质共存的可能性 结状神经节，(3)了解哪些迷走神经感觉递质产生 从哪个内脏器官，以及(4)关联神经递质 在存在适当发射机的情况下的定位数据 感受器。 荧光示踪技术将与免疫细胞化学相结合，以 确定包含给定参数的中枢和外周通路 神经递质。将对组织化学结果进行验证和量化 通过损伤细胞体区域和分析递质含量 显微解剖NTS。孤束核和孤束核内的神经递质受体 与迷走神经相关的感觉神经元将会用光定位 显微放射自显影。 这些研究将提供有关细胞神经生物学的信息。 内脏感觉神经元和NTS、CNS的递质系统 许多内脏反射的整合部位。此信息可能是 有助于最终理解自主神经控制的错乱 心血管、呼吸系统和胃肠系统。在……里面 此外，这些神经元的神经化学特征可能导致 自主神经障碍的药物治疗进展。

Visceral sensory neurons of the vagus nerve innervate the major organ systems of the thorax and abdomen. Vagal sensory neurons transmit information concerning such diverse stimuli as blood pressure, gastric distension, bronchiolar irritation and blood oxygenation to their termini in the nucleus tractus solitarius (NTS) in the brainstem. Whereas much is known about the sensory receptors, the neuroanatomic pathways of the afferent neurons and about their reflexes, the neurotransmitters contained in vagal sensory nerves are not well characterized. We propose to study the neurotransmitter system(s) associated with these neurons. Our preliminary work showed the presence of the putative neurotransmitter substance P (SP) in vagal afferent neurons (including baro- and chemoreceptor afferent fibers), and showed SP receptors in the NTS. Other evidence exists for cholecystokinin (CCK) and serotonin (5-HT) as potential transmitters in vagal sensory neurons. Therefore, we will simultaneously study these 3 transmitter systems (1) to localize the primary source of the agent in the NTS to peripheral or central neurons, (2) to investigate the possibility of transmitter coexistence in the vagal sensory cell bodies of the nodose ganglion, (3) to learn which vagal sensory transmitters arise from which visceral organs, and (4) to correlate the neurotransmitter localization data with the presence of the appropriate transmitter receptors. Fluorescent tracer techniques will be combined with immunocytochemistry to determine both the central and peripheral pathways which contain a given neurotransmitter. Histochemical results will be verified and quantitated by lesions of the cell body region and assays of the transmitter content of the microdissected NTS. The neurotransmitter receptors in the NTS and associated with vagal sensory neurons will be localized with light microscopic autoradiography. These studies will provide information on the cellular neurobiology of transmitter systems in visceral sensory neurons, and in the NTS, the CNS site of integration of numerous visceral reflexes. This information may be useful in ultimately understanding derangements of the autonomic control of the cardiovascular, respiratory and gastro-intestinal systems. In addition, neurochemical characterization of these neurons may lead to advances in drug therapy of autonomic disorders.