EXERCISE PRESSOR RESPONSES AND THE BRAINSTEM

运动加压反应和脑干

基本信息

批准号：
2218438
负责人：
GARY A. IWAMOTO
金额：
$ 8.45万
依托单位：
UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN
依托单位国家：
美国
项目类别：
财政年份：
1988
资助国家：
美国
起止时间：
1988-02-01 至 1999-12-31
项目状态：
已结题

项目摘要

The identification and specific role of the neurotransmitters involved in the central neural control of the circulation in perturbations such as exercise are topics of much experimentation and controversy at the present time. Resolution of these issues is important because our understanding of the central neural events behind autonomic control is incomplete without this information. Furthermore, the application of these data may lead to revisions in the pharmacological strategies for treatment of cardiovascular diseases. Some of the most critical areas of the central nervous system which participate in blood pressure (BP) and heart rate (HR) regulation are: 1) the intermediolateral cell column (IML) containing the cell bodies of the preganglionic sympathetic neurons and 2) various medullary areas, including the ventrolateral medulla (VLM), the raphe nuclei (RN) and the parapyramidal region of the,ventromedial medulla (VMM) which in turn are major medullary outflow pathways to the IML. The nature of chemical transmission within these areas are the focus of this proposal. It is a matter of common everyday experience that BP and HR are raised during exercise. This research will study models of neural mechanisms thought underlie these changes during exercise. One model is centrally mediated, relying on stimulation of the higher centers such as the hypothalamus to raise BP and HR. The other, the primary focus of this proposal, is a model of reflex mechanisms in exercise responses- stimulation of the ventral roots to induce muscular contraction (VRSMC), which in turn raises BP and HR. It is also important to study the transmitters mediating the reciprocal action (depressor) of the baroreceptor reflex (baroreflex) as it is thought to be inactivated during pressor events. Thus, we also wish to monitor the chemical events during the baroreflex-to determine the transmitters released due to an isolated baroreflex input so as to be aware of the significance of any changes in these transmitters during the pressor events associated with exercise. We will identify, using microdialysis and single cell recording combined with microiontophoresis: First, which substances are increased or attenuated at the level of the IML during: 1) VRSMC, 2) baroreflex stimulation and 3) stimulation of selected brainstem sites. Second, what chemicals are increased or attenuated at selected brainstem i pressor sites during: 1) VRSMC 2) baroreflex stimulation and 3) stimulation of selected diencephalic and other brainstem sites thought to modulate pressor information.

涉及的神经递质的识别和特定作用在扰动中循环的中心神经控制锻炼是实验和争议的主题现在的时间。解决这些问题很重要，因为我们理解自主控制背后的中心神经事件是没有这些信息不完整。此外，应用这些数据可能会导致对药理学策略的修订心血管疾病的治疗。一些最关键的领域参与血压（BP）的中枢神经系统和心率（HR）调节为：1）中间外侧细胞柱（IML）包含gangionic交感神经元的细胞体 2）包括腹侧髓质在内的各种髓质区域（VLM），raphe核（RN）和帕py骨区域腹侧髓质（VMM）又是主要的髓质流出通往IML的途径。这些内化学传输的性质领域是该提议的重点。 BP和人力资源培养是一个普遍的日常经验的问题锻炼期间。这项研究将研究神经机制的模型思想是在运动过程中这些变化的基础。一种模型是中央介导的，依靠较高中心的刺激下丘脑提高BP和HR。另一个，主要重点提案是运动反应中反射机制的模型 - 刺激腹根诱导肌肉收缩（VRSMC），这又提高了BP和人力资源。研究介导相互作用（抑郁剂）的发射机压力感受器反射（BaroreFlex）被认为是灭活的在施加事件中。因此，我们还希望监视化学事件在BaroreFlex期间，确定由于孤立的BaroreFlex输入，以意识到任何意义在与锻炼。我们将使用微透析和单细胞记录组合识别使用微滴虫：首先，哪种物质增加或在：1）VRSMC期间的IML级别减弱刺激和3）刺激选定的脑干部位。第二，什么化学物质在选定的脑干I压力上增加或减弱在以下位置：1）VRSMC 2）刺激性刺激和3）选定的双脑和其他脑干网站被认为是调节的施加信息。