CARBON DIOXIDE TRANSPORT AND CHEMOSENSITIVITY

二氧化碳传输和化学敏感性

• 批准号: 3340503
• 负责人: JEROME M ADAMS
• 金额: $ 3.74万
• 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: 1983-04-01 至 1986-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3340503
• 关键词: acid base balance; anions; brain stem; carbon dioxide transport; carbonate dehydratase; carbonic anhydrase inhibitors; chemoreceptors; computer data analysis; homeostasis; ion transport; membrane permeability; pulmonary respiration

An increase in the carbon dioxide concentration in arterial blood caused by disease or altered environment has a profound effect on breathing. The brain stem chemoreceptors thought to be primarily responsible are stimulated by hydrogen ion changes resulting from the reaction of CO2 with water in the tissue. This study is based on the hypothesis that catalysis of CO2 hydration by carbonic anhydrase in glial cells and transport of the resulting bicarbonate ions across the cellmembranes by a specific anion carrier system are cardinal steps in the function of the chemoreceptors. We propose to evaluate this hypothesis by experiments in anesthetized rats to measure the respiratory response to CO2. Inhibitors of catalysis and bicarbonate transport will be administered by perfusing the cerebrospinal fluid space of the brain stem. The parameters of a theoretical model of CO2 transport which includes the hydration reaction and carrier mediated HCO3 transport can then be statistically estimated from the experimental data and compared before and after inhibition of catalysis and transport. The results of this study will provide an understanding of the early events in the homeostasis of the brain acid-base environment and its effects on control of breathing.

动脉血中二氧化碳浓度升高是由于 疾病或环境改变对呼吸有深远的影响。 这 脑干化学感受器被认为主要负责的是 受到 CO2 反应产生的氢离子变化的刺激 组织中的水。 本研究基于催化假设 神经胶质细胞中碳酸酐酶对 CO2 的水合作用及其运输 通过特定阴离子产生的碳酸氢根离子穿过细胞膜 载体系统是化学感受器功能的主要步骤。 我们建议通过麻醉大鼠实验来评估这一假设 测量对 CO2 的呼吸反应。 催化抑制剂和 碳酸氢盐的运输将通过灌注脑脊液来管理 脑干的液体空间。 理论模型的参数 CO2 运输，包括水合反应和载体介导 然后可以从实验中统计估计 HCO3 传输 数据并比较催化和运输抑制前后。 这项研究的结果将提供对早期事件的理解 脑酸碱环境的稳态及其对 呼吸的控制。