CEPHALIC PHASE REFLEX PATHS IN THE DORSAL VAGAL COMPLEX

指导复杂神经电路运行的原理 脑干是神秘的，尽管它们在控制中至关重要。 人体内几乎所有主要的动态平衡功能。在 脑干、孤束核和背侧运动 迷走神经核(DMV)至关重要。NTS进程 来自身体广大区域的传入信息，与 其他脑干和前脑结构，并包含无数 神经递质。车管所是NTS的主要渠道 向主要器官系统发送副交感神经信号。为了获得 洞察这两个原子核如何整合代表 不同的感觉模式，这项研究将重点放在关系 在NTS传入的子集之间，那些起源于口腔的传入 腔，以及来自车管所的传出的子集，那些被定向到 隔下脏器。口腔感官刺激调节多种 通过激活副交感神经来实现胃肠功能 系统。这些“头相反射”可能是重要的启动和 优化消化过程和营养代谢。中环 支配这些反射的电路还没有被描述出来。 了解这个电路本身就很重要，因为它有 可能与消化和代谢功能紊乱有关。 口腔感觉信息直接上升到嘴侧NTS，并调节 肠道功能通过车管所。这个项目的长期目标是 是描述连接头端NTS和迷走神经的连接 运动神经元投射到隔膜下内脏。这些连接可以 包含了解头位相反射是如何组织的关键 并由脑干控制。具体目标是：(1)定位迷走神经 孤束核中由口感觉神经传入激活的运动神经元 (2)标记NTS前突触。 这些神经元的每一个的输入。对这些地图的比较将表明 迷走神经的输出受到感觉的离散组合的控制 投入。

The principles governing the operation of the intricate neural circuits in the brainstem are enigmatic, despite their vital importance in the control of virtually every major homeostatic function in the body. In the brainstem, the nucleus tractus solitarius (NTS) and the dorsal motor nucleus of the vagus (DMV) are of paramount importance. The NTS processes afferent information from vast regions of the body, communicates with other brainstem and forebrain structures, and contains a myriad of neurotransmitters. The DMV is the primary channel through which the NTS sends parasympathetic signals out to the major organ systems. To gain insight into how these two nuclei integrate information representing diverse sensory modalities, this study will focus on the relationship between a subset of the afferents to NTS, those originating from the oral cavity, and a subset of the efferents from DMV, those directed to the subdiaphragmatic viscera. Oral sensory stimulation modulates a variety of gastrointestinal functions by activating the parasympathetic nervous system. These "cephalic phase reflexes" may be important for priming and optimizing digestive processes and nutrient metabolism. The central circuitry governing these reflexes has not been characterized. Understanding this circuitry is important in itself because of its potential involvement in disorders of digestive and metabolic functions. Oral sensory information ascends directly to rostral NTS, and modulates enteric functions through the DMV. The long term objective of this project is to characterize the connections linking rostral NTS to vagal motoneurons projecting to subdiaphragmatic viscera. These connections may contain the key to understanding how cephalic phase reflexes are organized and controlled by the brainstem. Specific aims are: (1) to locate vagal motoneurons activated either by oral sensory afferents in the solitary tract, or by rostral NTS neurons, and (2) to map the NTS presynaptic inputs to each of these neurons. Comparison of these maps will indicate if vagal output is under the control of discrete combinations of sensory inputs.