MECHANISMS AND SITES OF VENTILATORY NEUROGENESIS

描述：（改编自申请人摘要）通气活动 可以在多个脑干部位产生。 喘息声被记录下来 在分离脑桥和髓质之后。 外侧区 被盖区被假设包含中央模式发生器 它含有起搏器元件。 研究将评估 通过表征神经元活动来进一步这些假设， 传入和传出投射。 喘息的评价 可以提供洞察神经发生的所有模式的自动 净化活动。 即使起搏器元件确实是诱发性神经发生的基础， 回路定义了吸气和呼气的相位周期和形状 调制神经放电模式。 在这种情况下，神经元 脑桥嘴侧“呼吸调节中枢”的功能 解释性控制，可能还有神经发生。 这些功能包括 吸气的开始和终止，中枢神经系统的整合 化学感受器传入刺激和脊髓呼气神经的发作 活动 假设将被评估，这些多功能 是由呼吸调节系统内的不同亚群调节的。 亚群问题也将在关于下列问题的研究中加以审查： 负责定义呼气的神经回路 活动 最近的证据表明，神经呼气可能是 分为两个阶段。 定义这些阶段的一个关键作用是 通过吸气后神经元的放电来锻炼。 然而，在这方面， 关于这些神经元活动的信息是相互矛盾的。 这 相互矛盾的信息可能反映了亚群的存在。 的 将评估一些吸气后神经元被 前运动神经元到咽或喉运动神经元，而其他参与 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个神经回路，这是至关重要的 仅用于脊神经的呼气活动。 这条线路，包括 小脑的小脑下核，被假设为调节 脊髓运动神经元活动的途径，绕过延髓 呼吸核 该回路中的活动可以提供 关于脊髓神经调节的几个谜团的解释 呼气活动，包括姿势的影响和 消除这些活动，但不是球脊髓呼气 神经元，麻醉。

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.