Effect of temperature on rate of CO2 uptake by human red cell suspensions.
Effect of temperature on rate of CO2 uptake by human red cell suspensions.
复制标题
温度对人红细胞悬浮液吸收 CO2 速率的影响。
DOI：
10.1152/ajplegacy.1975.228.5.1589
复制
发表时间：
1975
期刊：
影响因子：
--
通讯作者：
R. Forster
中科院分区：
文献类型：
--
作者：
R. Holland;R. Forster
在Hartridge-Roughton连续流快速反应装置中，使用CO2电极跟踪人红细胞含氧悬浮液摄取二氧化碳的时间过程。在11 ℃至42 ℃的几个温度下进行测量，反应混合物中的初始PCO 2为40至60 mmHg。摄取曲线的初始部分大概是速率限制的细胞内水合CO2与反应速度常数在细胞水从280至960 S-1，在42 ℃和2.4千卡mol-1的活化能。CO2吸收的后期阶段要慢得多，半衰期从12摄氏度时的1.5秒到42摄氏度时的0.7秒，并且可能受到氯化物-碳酸氢盐移位和H+交换的速率限制。结果表明，尽管细胞水的水合反应在37摄氏度时加速了5,000倍，在42摄氏度时加速了3,800倍，但交换的后期部分太慢，以至于血液无法进入CO2，在其通过毛细血管床期间与积极锻炼的肌肉平衡。
The time course of carbon dioxide uptake by oxygenated supensions of human red cells was followed using a CO2 electrode in a Hartridge-Roughton continuous-flow rapid-reaction apparatus. Measurements were made at several temperatures from 1i to 42 degrees C, with the initial PCO2 in the reacting mixture from 40 to 60 mmHg. The initial part of the uptake curve is presumably rate limited by the intracellular hydration of CO2 with reaction-velocity constants in cell water from 280 to 960 S-1 at 42 degrees C and an activation energy of 2.4 kcal mol-1. The later stages of CO2 uptake were much slower, with half-times from greater than 1.5 s at 12 degrees C to 0.7 s at 42 degrees C, and were presumably rate limited by the chloride-bicarbonate shift and H+ interchanges. The results indicate that despite the acceleration of the hydration reaction in cell water by a factor of 5,000 at 37 degrees C and 3,800 at 42 degrees C, the later part of the exchange is too slow to permit blood to come intoC02, equilibrium with actively exercising muscles during its passage through the capillary bed.