EXERCISE PRESSOR RESPONSES AND THE BRAINSTEM

运动加压反应和脑干

• 批准号: 3353020
• 负责人: GARY A. IWAMOTO
• 金额: $ 7.87万
• 依托单位: UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-02-01 至 1996-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3353020
• 关键词: acetylcholine; aspartate; baroreceptors; baroreflex; blood pressure; brain stem; cats; chemoreceptors; dorsal raphe nucleus; electrophysiology; electrostimulus; enkephalins; exercise; glutamates; heart rate; high performance liquid chromatography; histochemistry /cytochemistry; microdialysis; muscle contraction; neural information processing; neural transmission; neurotransmitter metabolism; nontherapeutic iontophoresis; single cell analysis; substance P

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.

神经递质的识别和特定的作用 在扰动中循环的中枢神经控制，如 运动是许多实验和争议的话题 现在的时间。这些问题的解决很重要，因为我们的 对自主控制背后的中枢神经事件的理解是 没有这些信息是不完整的。此外，该技术的应用 这些数据可能会导致对药物治疗策略的修订 心血管疾病的治疗。一些最关键的领域 中枢神经系统参与血压(BP)和 心率(HR)的调节有：1)中间外侧细胞柱 (IML)含有节前交感神经元胞体 2)各种延髓区域，包括延髓腹外侧区 (VLm)、中缝核群(RN)和丘脑束旁核群。 延髓腹内侧部(VMM)是主要的髓质流出物 通向IML的路径。它们内部的化学传播的性质 这些领域是这项提案的重点。 BP和HR被抬高是日常生活中常见的事情 在锻炼的时候。本研究将研究神经机制的模型。 在锻炼过程中，思维是这些变化的基础。其中一个模型集中在 调节，依赖于更高中枢的刺激，如 下丘脑升高血压和心率。另一个，这个的主要焦点 是运动反应中反射机制的模型-- 刺激腹根诱发肌肉收缩(VRSMC)， 这反过来又增加了BP和HR。此外，研究 调节神经递质相互作用(抑制器)的递质 压力感受器反射(压力感受器反射)，因为它被认为是失活的 在加压事件期间。因此，我们也希望监测化学事件 在压力反射期间-以确定由于 隔离的压力反射输入，以便意识到任何 在与以下相关的加压事件期间，这些递质的变化 锻炼身体。 我们将使用微透析和单细胞记录相结合的方法进行鉴定 微离子导入：首先，哪些物质增加或 在IML水平上衰减：1)VRSMC，2)压力反射 刺激和3)选择脑干部位的刺激。第二，什么 化学物质在选定的脑干I升压区增加或减弱 部位：1)VRSMC 2)压力感受性反射刺激3)刺激 选定的间脑和其他脑干部位被认为是调节 加压信息。