CARBON DIOXIDE TRANSPORT AND CHEMOSENSITIVITY

动脉血中二氧化碳浓度的增加 疾病或环境变化对呼吸有深远的影响。这个 脑干化学感受器被认为是主要负责的 受二氧化碳与氢离子反应产生的氢离子变化的刺激 纸巾里有水。这项研究是基于这样一种假设：催化 神经胶质细胞中碳酸酐酶对二氧化碳水合作用的影响及其转运 一种特定的阴离子在细胞膜上产生碳酸氢根离子 载体系统是化学感受器发挥作用的重要步骤。 我们建议通过麻醉大鼠的实验来评估这一假说。 以测量对二氧化碳的呼吸反应。催化和抗肿瘤药物 碳酸氢盐的运输将通过脑脊液灌流来实施 脑干的液体空间。一个理论模型的参数 包括水合反应和载体介导的二氧化碳传输 然后可以从实验中对HCO3的传输进行统计估计 并对抑制前后的催化和转运数据进行比较。 这项研究的结果将提供对早期事件的理解 脑内酸碱环境的动态平衡及其对脑功能的影响 控制呼吸。

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.