MEDULLARY MECHANISMS OF RESPIRATORY CONTROL

这项研究计划的长期目标是了解 细胞和突触机制参与产生和 控制哺乳动物的呼吸节律。 很显然， 呼吸对于维持生命本身是必不可少的，因此， 了解呼吸节律的起源和调节 具有重要的生理意义 呼吸 节律是由体内的神经回路产生和控制的。 但负责这种节律的机制 一直是个谜 呼吸神经元集中在 分为两组 这些团体被称为 背侧呼吸组（DRG）和腹侧呼吸组 （VRG）。 本建议书是一个项目的竞争性更新， 体外脑干切片制备，以表征 延髓呼吸系统的细胞和形态学特性 这些群体中的神经元。 在上一个资助期内，我们 改进了脑干切片的制备，并利用它来 研究背根神经节神经元的特性。 蜂窝 VRG中神经元的性质，这是最大的一组 延髓中的呼吸神经元，实际上是未知的。 的 VRG从脊髓的嘴侧延伸到脊髓的背侧。 脑桥-延髓边界并包围疑核 以及波青格氏综合症。 我们的具体目标是：1. 表征 VRG内神经元的电生理特性， 细胞内记录以量化内在细胞特性， 为了确定神经元的类别是否可以由这些定义， 特性. 2. 为了表征 荧光黄染色观察VRG神经元 或辣根过氧化物酶（HRP）。 3. 是VRG的特性 神经元被神经递质修饰， 呼吸？ 候选的神经递质包括促甲状腺激素- 释放激素血清素和P物质 使用dual 细胞内记录，以量化突触之间的相互作用 DRG和VRG神经元。

The long term goal of this research program is to understand the cellular and synaptic mechanisms involved in generating and controlling the mammalian respiratory rhythm. Clearly, breathing is essential to the maintenance of life itself, therefore, understanding the origin and regulation of the respiratory rhythm is of fundamental physiological importance. The respiratory rhythm is generated and controlled by a neuronal circuit within the brainstem but the mechanisms responsible for this rhythm have remained a mystery. Respiratory neurons are concentrated in two groups within the medulla. These groups are called the dorsal respiratory group (DRG) and the ventral respiratory group (VRG). This proposal is a competitive renewal for a project using an in vitro brainstem slice preparation to characterize the cellular and morphological properties of medullary respiratory neurons within these groups. During the previous grant period we refined the brainstem slice preparation and have exploited it to study the properties of neurons in the DRG. The cellular properties of neurons in the VRG, which is the largest group of respiratory neurons in the medulla, are virtually unknown. The VRG extends from the rostral reaches of the spinal cord to the ponto-medullary border and encompasses the nucleus ambiguus and retroambiguus as well as Botzinger's complex. Our specific aims are: 1. To characterize the eloctrophysiological properties of neurons within the VRG using intracellular recording to quantify intrinsic cellular properties and to determine if classes of neurons can be defined by these properties. 2. To characterize the morphological properties of neurons in the VRG by intracellular staining with Lucifer yellow or horseradish peroxidase (HRP). 3. Are the properties of VRG neurons modified by neurotransmitters known to influence respiration? Candidate neurotransmitters include thyrotropin- releasing hormone, serotonin, and substance P. 4. To use dual intracellular recording to quantify synaptic interactions between DRG and VRG neurons.