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。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 具有基本的生理重要性。呼吸系统 节律是由体内的神经元电路产生和控制的 脑干，但负责这种节奏的机制 一直是个谜。呼吸神经元集中 在延髓内分成两组。这些组被称为 背侧呼吸组(DRG)和腹侧呼吸组 (VRG)。此建议书是针对使用以下技术的项目的竞争性续订 一种体外脑干切片的制备方法 延髓呼吸系统的细胞和形态特征 这些组内的神经元。在之前的授权期内，我们 改进了脑干切片的制备方法，并利用它 研究背根神经节中神经元的特性。蜂窝手机 VRG中神经元的特性，这是最大的一组 延髓中的呼吸神经元几乎是未知的。这个 VRG从脊髓的吻端延伸到 桥-髓边界，包围疑核 以及后歧义和波辛格情结。 我们的具体目标是：1.描述 VRG内神经元的电生理特性 细胞内记录以量化固有的细胞属性和 为了确定神经元的类别是否可以由这些 属性。2.表征植物的形态特征 荧光黄细胞内染色显示视网膜节内神经元 或辣根过氧化物酶(HRP)。3.VRG的属性是什么 已知由神经递质修饰的神经元影响 呼吸？候选神经递质包括促甲状腺激素- 释放激素、5-羟色胺和P物质4.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.