MECHANISMS AND SITES OF VENTILATORY NEUROGENESIS

描述：(改编自申请者的摘要)呼吸机活动 可以在多个脑干部位产生。喘息被记录下来 在分离出延髓和脑桥之后。侧面的一个区域 假设被盖域包含中央图案生成器 用于喘息，其中含有起搏器元素。研究将评估 进一步的这些假设通过表征神经元活动和 来自该区域的传入和传出投射。对喘息的评估 可能提供对所有类型的自动的神经发生的洞察 换气活动。 即使起搏器元素确实是呼吸性神经发生的基础，神经元 电路定义了吸气、呼气和形状的阶段 呼吸调节的神经放电模式。在这种情况下，神经元 吻侧脑桥“肺中枢”的多项功能 呼吸控制，可能还有神经发生。这些功能包括 灵感的开始和终止，中枢的整合 化学感受器传入刺激与脊髓呼气神经的起始 活动。这一假设将被评估为这些多重功能 在肺气肿系统中由不同的亚群调节。 亚群问题也将在关于以下方面的研究中进行研究 负责定义呼气的神经回路 活动。最近的证据表明，神经末梢可能是 分为两个阶段。定义这些阶段的一个关键角色是 通过吸气后神经元的放电来锻炼。然而， 关于这些神经元活动的信息是相互矛盾的。这 相互冲突的信息可能反映了亚群体的存在。这个 一些吸气后神经元的假说将会得到评估 咽部或喉部运动神经元的运动前神经元，而其他的受累 在整个呼吸控制的呼气活动的定义中 系统。 最后的研究将描述一种至关重要的神经元回路 仅适用于脊神经的呼气活动。这条赛道，涉及 小脑小脑下核，被认为是为了调节 绕过延髓的脊髓运动神经元活动 呼吸核团。此电路内的活动可能会提供 解开脊髓调节的几个谜团 呼气活动，包括姿势和呼吸的影响 消除这些活动，但不消除球脊呼气的活动 麻醉状态下的神经元。

DESCRIPTION: (adapted from the applicant's abstract) Ventilatory activity can be generated at multiple brainstem sites. Gasping is recorded following the isolation of medulla from pons. A region of the lateral tegmental field is hypothesized to contain the central pattern generator for gasping, which contains pacemaker elements. Studies will evaluate further these hypotheses by characterizing the neuronal activities and afferent and efferent projections from this region. Evaluations of gasping may provide insights into the neurogenesis of all patterns of automatic ventilatory activity. Even if pacemaker elements do underlie ventilatory neurogenesis, neuronal circuits define the phasic periods of inspiration and expiration and shape respiratory-modulated neural discharge patterns. In this context, neurons of the rostral pontile "pneumotaxic center" exercise multiple functions in ventilatory control and, possibly, neurogenesis. Such functions include the onset and terminations of inspiration, integration of central chemoreceptor afferent stimuli, and onset of spinal expiratory neural activities. The hypothesis will be evaluated that these multiple functions are regulated by different subpopulations within the pneumotaxic system. The question of subpopulations will also be examined in studies concerning the neural circuit which is responsible for the definition of expiratory activities. Recent evidence has demonstrated that neural expiration may be divided into two phases. A critical role in defining these phases is exercised by the discharge of post-inspiratory neurons. However, information concerning these neuronal activities is conflicting. This conflicting information may reflect the existence of subpopulations. The hypothesis will be evaluated that some post-inspiratory neurons are premotor to pharyngeal or laryngeal motoneurons whereas others are involved in the definition of expiratory activity for the entire ventilatory control system. The final studies will characterize a neuronal circuit which is critical only for expiratory activities of spinal nerves. This circuit, involving the infracerebellar nucleus of the cerebellum, is hypothesized to regulate spinal motonueronal activities by a pathway which bypasses the medullary respiratory nuclei. Activity within this circuit may provide an explanation for several enigmas concerning the regulation of spinal expiratory activities, including the influence of posture and the elimination of these activities, but not those of bulbospinal expiratory neurons, in anesthesia.