CNS SEROTONERGIC NEURONS AND BREATHING

关于中枢神经系统的现有知识 控制呼吸的神经通路和神经递质 不完整 我们一直在使用神经解剖学和 神经药理学技术，以扩大我们的 并发现刺激尾部 中缝核产生呼吸运动流出的变化， 膈神经和喉返神经介导的 肾上腺素能神经通路。 本报告的总体目标 我们的建议是研究肾上腺皮质激素能神经元的作用， 中缝尾侧核在猫呼吸控制中的作用 具体目标是：1）识别尾侧的连接 中缝核与其他已建立的呼吸核，包括 背侧呼吸组、腹侧呼吸组、Botzinger 复合体、脑桥呼吸组和喉返神经 疑核运动神经元; 2）确定血清素是否 一种神经递质，用于中缝尾侧投射到这些 呼吸核; 3）确定血清素是否支配 在这些呼吸神经元中， 核;和4）确定血清素参与 介导膈神经和喉返神经的变化 刺激中缝尾核引起的神经活动。 所用方法包括：用凝集素顺行追踪， 荧光染料逆行追踪，免疫组织化学， 膈神经记录，喉返神经记录， 电和化学（L-谷氨酸）刺激脑核， 呼吸神经元活动的细胞外记录，以及 压力显微注射影响肾上腺素能活性的药物。 迫切需要进行进一步的基础研究， 突触关系和中枢神经递质 呼吸神经元 这项研究也具有临床意义 随着对呼吸道疾病的神经化学基础的了解的增加， 控制将增加改善的可能性 呼吸系统疾病的药物干预，包括 睡眠呼吸暂停、婴儿猝死综合征和慢性阻塞性肺疾病 肺部疾病。

Current knowledge concerning the central nervous system neuropathways and neurotransmitters controlling respiration is incomplete. We have been using neuroanatomical and neuropharmacological techniques in order to extend our knowledge in this area and found that stimulation of the caudal raphe nuclei produces changes in respiratory motor outflow of the phrenic and recurrent laryngeal nerves that are mediated by serotonergic neuropathways. The overall objective of this proposal is to investigate the role of the serotonergic neurons of the caudal raphe nuclei in respiratory control in the cat. The specific aims are to: 1) Identify the connections of the caudal raphe nuclei with other established respiratory nuclei including the dorsal respiratory group, ventral respiratory group, Botzinger Complex, pontine respiratory group and recurrent laryngeal nerve motoneurons of the nucleus ambiguus; 2) Determine if serotonin is a neurotransmitter used by caudal raphe projections to these respiratory nuclei; 3) Determine if serotonin innervates functionally identified respiratory neurons in these respiratory nuclei; and 4) Determine the involvement of serotonin in mediating the changes in phrenic nerve and recurrent laryngeal nerve activity evoked by stimulation of the caudal raphe nuclei. Methods to be used include: anterograde tracing with lectin, retrograde tracing with fluorescent dyes, immunohistochemistry, phrenic nerve recording, recurrent laryngeal nerve recording, electrical and chemical (L-glutamate) stimulation of brain nuclei, extracellular recording of respiratory neuron activity, and pressure microinjection of drugs affecting serotonergic activity. There is a critical need for further basic research to define the synaptic relationships and neurotransmitters of central respiratory neurons. This research is of clinical importance also as increased knowledge of the neurochemical basis of respiratory control will increase the possibilities of improving pharmacological intervention in respiratory disorders including sleep apnea, sudden infant syndrome and the chronic obstructive pulmonary diseases.