ORGANIZATION OF THE SPINAL CORD

这项建议的目标是确定神经回路 以及产生一种广义状态的细胞机制 七鳃鳗大脑的兴奋性增强。此活动状态为 被认为是脊椎动物脑干唤醒的模型。这个 七鳃鳗脑干在本研究中的优势在于 相对简单，与其他组织原则相似 脊椎动物，分离制剂产生的能力 与行为相对应的活动，同时要 适用于细胞内录音和药理学 调制，以及P.I.对子系统的背景研究 它们都处于活动状态。 七鳃鳗在体外和体内的脑表现为静息状态 和活动状态。在体外发生活跃的发作或对 感觉刺激，并表现为活动增加在 三叉神经和脊髓运动通路的增强率和强度 虚构的呼吸，并改变了对感官刺激的反应。 活体内相应的行为变化是主动依恋 通过吸盘，呼吸频率，身体运动的变化，以及 改变了对振动的反应。 这项建议的策略是：(A)利用已知的组织 三叉神经、呼吸、网状脊髓和感觉系统 在脑干中检测体内的行为变化和 活动状态下的体外神经生理变化，(B)至 使用损伤、细胞外记录和局灶性刺激 定位参与活动状态的关键大脑区域，(C) 使用受体激动剂和拮抗剂，包括胆碱能和 胺能药物，启动或阻断活性成分 体外状态，(D)使用来自目标的细胞内记录 神经元来确定细胞属性的变化和 激活状态期间的单突触传递，(E)识别 参与活动状态的脑干中间神经元， 以及(F)将这些信息整合为与蜂窝和电路有关的信息 在类似觉醒状态下的神经调制模型 一种简单脊椎动物的孤立脑干。

The objective of this proposal is to determine the neural circuits and cellular mechanisms which produce a state of generalized enhanced excitability in the lamprey brain. This active state is proposed as a model for arousal in the vertebrate brain stem. The advantages of the lamprey brain stem for this study are its relative simplicity, similar principles of organization as in other vertebrates, the ability of the isolated preparation to produce activities corresponding to behavior and at the same time to be suitable for intracellular recordings and pharmacological modulation, and background studies by the P.I. on the subsystems which are involved in the active state. The lamprey brain in vitro and lampreys in vivo display resting and active states. Active episodes in vitro occur or in response to sensory stimuli and are expressed as increased activities in trigeminal and spinal motor pathways, enhanced rate and intensity of fictive breathing, and altered responsiveness to sensory stimuli. Corresponding behavioral changes in vivo are active attachment by the sucker, changes in breathing rate, body movements, and altered responsiveness to vibration. The strategy of this proposal is (a) to use the known organization of the trigeminal, respiratory, reticulospinal, and sensory systems in the brain stem to assay behavioral changes in vivo and neurophysiological changes in vitro during the active state, (b) to use lesions, extracellular recording, and focal stimulation to localize critical brain regions involved in the active state, (c) to use receptor agonists and antagonists, including cholinergic and aminergic drugs, to initiate or block components of the active state in vitro, (d) to use intracellular recordings from target neurons to determine changes in cellular properties and monosynaptic transmission during the active state, (e) to identify brain stem interneurons which are involved in the active state, and (f) to integrate this information as cellular and circuit-related models for neural modulation during an arousal-like state in the isolated brain stem of a simpler vertebrate.