EXERCISE PRESSOR RESPONSES AND THE BRAINSTEM

运动加压反应和脑干

• 批准号: 3353022
• 负责人: GARY A. IWAMOTO
• 金额: $ 7.21万
• 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 1990-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3353022
• 关键词: baroreceptors; brain stem; cats; chemoreceptors; dyes; electrophysiology; epinephrine; exercise; histochemistry /cytochemistry; hypothalamus; muscle contraction; neural transmission; neurosurgery; norepinephrine; reflex; single cell analysis; subthalamus; tyrosine 3 monooxygenase; vasomotion

Isometric muscular exercise causes increases in heart rate, blood pressure and ventilation. At least part of this response in reflexly evoked. This reflex may be conveniently studied in acute animal utilizing stimulation of cut ventral roots to achieve muscular contraction which in turn evokes a cardiovascular response similar in many ways to that observed during isometric exercise. This reflex is often called the "exercise pressor reflex" as a convenient operational definition. The proposed research will investigate the specific location, electrophysiological response characteristics and immunocytochemical properties of cells which may contribute to the reflex. Brainstem areas for study include: (a) caudal ventrolateral medulla including the area in or near the lateral reticular nucleus (LRN) and the nucleus ambiguus (NA), (b) rostral ventrolateral medulla including the areas analogous to the C1 areas in the rat, and (c) medial medulla including the "dorsomedial pressor region", the nucleus of the tractus solitarius and the inferior olive. The cells of these areas will be evaluated for responses to: (1) muscular contraction, (2) baroreceptor input, (3) chemoreceptor input, (4) stimulation of the "subthalamic locomotor area", or "defence area", and also will be evaluated for (5) contribution to tonic sympathetic outflow, and (6) epinephrine and norepinephrine content. It is though that a fundamental reciprocal inhibition relationship might exist between the muscular contraction- evoked pressor reflex and various depressor reflexes; and therefore, key points in both types of reflexes will be studied. The main analysis techniques will include the use of 1) single cell electrical recording 2) immunocytochemical labelling for tyrosine hydroxylase (TH) and phenylethanolamine-N- methyltransferase (PNMT). The studies will yield a further understanding of processes underlying pressor reflexes and their reciprocal relationship with depressor reflexes.

等长肌肉锻炼会增加心率，血液 压力和通风。 至少部分回应是 反射性地唤起。 这种反射可以方便地在 急性动物利用刺激切断的腹根， 肌肉收缩引起心血管 在许多方面与等长收缩时观察到的反应相似 锻炼的 这种反射通常被称为“运动加压反射” 作为一个方便的操作定义。 拟议研究 将调查具体位置，电生理 免疫细胞化学特性 可能有助于反射的细胞。 脑干区域 研究包括：（a）尾侧腹外侧髓质，包括 外侧网状核（LRN）内或附近的区域和 疑核（NA），（B）延髓头端腹外侧区 包括与大鼠中的C1区类似的区域，以及（c） 内侧髓质包括“背内侧加压区”， 孤束核和下橄榄核。 细胞 将评价这些区域的反应：（1）肌肉 收缩，（2）压力感受器输入，（3）化学感受器输入，（4） 刺激“丘脑底运动区”或“防御 区域”，并且还将评估（5）对主音的贡献 交感神经流出;（6）肾上腺素和去甲肾上腺素 内容 这是一个基本的相互抑制， 肌肉收缩之间可能存在关系- 诱发升压反射和各种降压反射;以及 因此，将研究这两种反射类型的关键点。 主要的分析技术将包括使用1）单细胞 电记录2）免疫细胞化学标记 酪氨酸羟化酶（TH）和苯乙醇胺-N- 甲基转移酶（PNMT）。 这些研究将产生进一步的 了解升压反射的潜在过程及其 与降压反射的相互关系。