MEDULLARY CHEMORECEPTOR PHYSIOLOGY

髓质化学感受器生理学

• 批准号: 3340820
• 负责人: JEROME M ADAMS
• 金额: $ 6.75万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 1983
• 资助国家: 美国
• 起止时间: 1983-09-01 至 1987-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3340820
• 关键词: acidity /alkalinity; anions; arterioles; carbon dioxide transport; cerebrospinal fluid; chemoreceptors; homeostasis; ion transport; mathematical model; microelectrodes; neurophysiology; perfusion; phrenic nerve; pulmonary respiration; respiratory gas level

Rational treatment of respiratory disease, especially acute respiratory failure and CO2 retention in chronic diseases, is based on the understanding of CO2 control of breathing. The medullary chemoreceptors play a crucial role in regulating breathing but the mechanisms governing their activity are not established. The relation between hydrogen ion activity in medullary chemoreceptor tissue and phrenic nerve activity will be studied in anesthetized rats and cats by measuring tissue pH with a pH microelectrode during changes of arterial PCO2 and PO2. The possibility of trans-arteriolar CO2 exchange during high flow CSF perfusion will be tested by measuring tissue pH while changing arterial and CSF perfusate PCO2 in the same and in opposing directions. By measuring local tissue perfusion with a servo controlled temperature probe, with simultaneous measure of tissue pH, the response of blood flow in the chemoreceptor tissue to changes of PO2 and PCO2 and its relation to tissue hydrogen ion activity will be studied. The effect on tissue pH of the carrier mediated exchange of HCO3- across cells will be studied by measuring tissue pH response to altering arterial PCO2 before and after pharmacologic block of the HCO3 carrier. Yamamoto's hypotheses concerning the generation of CO2 by respiratory neuron activity and consequent chemoreceptor stimulation will be tested by measuring chemoreceptor pH during stimulation of the carotid sinus nerves. These studies should provide evidence to reject or accept hypotheses of chemoreceptor mechanisms which are of cardinal importance.

呼吸道疾病的合理治疗，尤其是急性呼吸道 慢性疾病中的失败和二氧化碳保留是基于 了解二氧化碳控制呼吸。 髓质化学感受器 在调节呼吸方面起着至关重要的作用 他们的活动没有建立。 氢离子之间的关系 髓质化学感受器组织和神经神经活性的活性将 通过用pH测量组织pH在麻醉大鼠和猫中进行研究 动脉PCO2和PO2变化期间的微电极。 可能的可能性 高流量CSF灌注期间将测试跨性别二氧化碳二氧化碳交换 通过在改变动脉和CSF灌注液PCO2时测量组织pH 相同和在相反的方向上。 通过测量局部组织灌注 用伺服控制的温度探针，同时衡量 组织pH，化学感受器组织中血流的反应 PO2和PCO2的变化及其与组织氢离子活性的关系 将被研究。 对载体介导的交换的组织pH的影响 通过测量组织pH响应对 在HCO3的药理块之前和之后改变动脉PCO2 载体。 Yamamoto关于二氧化碳产生的假设 呼吸神经元活性和随之而来的化学感受器刺激将 通过测量颈动脉刺激期间的化学感受器pH测试 窦神经。 这些研究应提供拒绝或接受的证据 基本重要性的化学感受器机制的假设。