Influence of carbon dioxide kinetics on pulmonary carbon dioxide exchange.
Influence of carbon dioxide kinetics on pulmonary carbon dioxide exchange.
复制标题
二氧化碳动力学对肺二氧化碳交换的影响。
DOI：
10.1152/jappl.1993.74.2.715
复制
发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Klocke,RA
中科院分区：
文献类型：
--
作者：
Schunemann,HJ;Klocke,RA
在红细胞缺乏的情况下，定位于肺毛细血管内皮的碳酸酐酶（CA）催化碳酸氢盐脱水成二氧化碳。我们研究了肺CA和CO2对缓冲液灌注的离体肺CO2排泄的影响。在指示剂稀释实验中，与血管指示剂相比，静脉流出物中溶解的CO2和乙炔（C2H2）的回收明显延迟，因为气体分布在血管和肺泡体积中。在第二组实验中，在注射含有溶解的二氧化碳或碳酸氢盐的丸剂后，用容积描记法监测二氧化碳排泄动力学。交换与溶出C2H2的排泄进行比较。溶解的CO2和C2H2的排泄速率相同，表明CO2作为惰性气体以相同的方式进行交换。当注入碳酸氢盐时，CO2排泄比C2H2排泄滞后约0.3 s。用乙酰唑胺抑制肺CA使CO2交换量减少到对照的四分之一，并使交换延迟减少一半。
In the absence of erythrocytes, carbonic anhydrase (CA) localized to the pulmonary capillary endothelium catalyzes the dehydration of bicarbonate to CO2. We studied the effects of lung CA and the reactions of CO2 on CO2 excretion in isolated lungs perfused with buffer. In indicator-dilution experiments, recoveries of dissolved CO2 and acetylene (C2H2) in the venous effluent were delayed significantly compared with a vascular indicator because the gases were distributed in both the vascular and alveolar volumes. In a second group of experiments, the kinetics of CO2 excretion were monitored with a plethysmographic method after injection of a bolus containing dissolved CO2 or bicarbonate. Exchange was compared with excretion of dissolved C2H2. The rate of excretion of dissolved CO2 and C2H2 was identical, indicating that CO2 is exchanged in the same manner as an inert gas. When bicarbonate was injected, CO2 excretion lagged behind C2H2 excretion by approximately 0.3 s. Inhibition of lung CA with acetazolamide reduced the quantity of CO2 exchanged to one-fourth of control and decreased the delay in exchange by one-half.