CO2 TRANSPORT AND MEDULLARY CHEMORECEPTOR PHYSIOLOGY

二氧化碳传输和髓质化学感受器生理学

• 批准号: 3073666
• 负责人: JEROME M ADAMS
• 金额: $ 5.14万
• 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 1988-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3073666
• 关键词: acidity /alkalinity; anions; arterioles; carbon dioxide transport; carbonate dehydratase; chemoreceptors; dyes; homeostasis; mathematical model; microelectrodes; neurophysiology; perfusion; phrenic nerve; pulmonary respiration; vascular endothelium permeability

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 role of catalysis of CO2 hydration in producing hydrogen ions and of anion (HCO3) exchange across cells (buffering this process) will be studied in anesthetized rats by administering blocking agents of these processes via CSF perfusion into the cisterna magna and measuring the ventilatory response to CO2. The relation between hydrogen ion activity in medullary chemoreceptor tissue and ventilation will be studied in anesthetized rats and cats by measuring tissue pH with a pH microelectrode inserted in the tissue and phrenic nerve activity during transient changes of arterial PCO2 and PO2. 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 possibility of trans-arteriolar CO2 exchange will be tested by measuring tissue pH while changing arterial and CSF superfusate PCO2 in the same and in opposing directions. Theoretical description of CO2 transport in chemoreceptor tissue will focus on anion exchange, buffering and arteriolar exchange. 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。 CO2水合催化的作用 在产生氢离子和跨细胞的阴离子（HCO3）交换时 （缓冲此过程）将在麻醉大鼠中研究 通过CSF灌注对这些过程的阻断剂进行管理 Cisterna Magna并测量对CO2的通气响应。 关系 在髓质化学感受器组织中的氢离子活性与 通过测量，将在麻醉大鼠和猫中研究通风 组织pH和pH微电极插入在组织中和神经神经 动脉PCO2和PO2瞬时变化期间的活性。 通过测量 用伺服控制的温度探针，局部组织灌注， 同时衡量组织pH，血液流动的反应 化学感受器组织对PO2和PCO2的变化及其与组织的关系 将研究氢离子活性。 跨性别的可能性 二氧化碳交换将通过测量组织pH进行测试 和CSF超级偶然的PCO2在相同的方向上。 化学感受器组织中二氧化碳转运的理论描述将聚焦 在阴离子交换，缓冲和小动脉交换上。 这些研究应该 提供拒绝或接受化学感受器机制的假设的证据 这很重要。