Böning D, Schünemann H J, Maassen N, Busse M W
Department of Sports and Exercise Physiology, Medical School Hannover, Germany.
J Appl Physiol (1985). 1993 Feb;74(2):710-4. doi: 10.1152/jappl.1993.74.2.710.
The influence of lactic acid, hydrochloric acid, and sodium lactate addition (10 mmol/l each) on oxylabile CO2 was investigated in blood of male subjects after equilibration at 37 degrees C with 3, 6, and 10% CO2 in N2 and O2, respectively. The total CO2, pH in whole blood and erythrocytes, oxygen saturation, hemoglobin concentration, and hematocrit value were measured. With these data we calculated bicarbonate and carbamate concentrations and the corresponding differences between oxygenated and deoxygenated blood. The amount of oxylabile bicarbonate was not systematically influenced by the various experimental conditions. The carbamate content, however, was larger in deoxygenated than in oxygenated blood (up to 0.08 mol/mol hemoglobin) only in the absence of lactate. In the presence of lactic acid as well as sodium lactate, the carbamate content in oxygenated blood was higher by 0.06-0.13 mol/mol hemoglobin than in deoxygenated blood. The lactate effect even increased after 2,3-diphosphoglycerate depletion. We suggest, therefore, a competition between CO2 and the lactate ion at the NH2-terminal valine of the beta-globin chain in deoxygenated hemoglobin.
分别在37℃下用3%、6%和10%的二氧化碳与氮气和氧气平衡后，研究了向男性受试者血液中添加乳酸、盐酸和乳酸钠（各10 mmol/L）对氧不稳定二氧化碳的影响。测量了总二氧化碳、全血和红细胞中的pH值、氧饱和度、血红蛋白浓度和血细胞比容值。利用这些数据，我们计算了碳酸氢盐和氨基甲酸盐的浓度以及氧合血和脱氧血之间的相应差异。各种实验条件对氧不稳定碳酸氢盐的量没有系统性影响。然而，仅在不存在乳酸的情况下，脱氧血中的氨基甲酸盐含量比氧合血中的高（高达0.08 mol/mol血红蛋白）。在存在乳酸和乳酸钠的情况下，氧合血中的氨基甲酸盐含量比脱氧血中的高0.06 - 0.13 mol/mol血红蛋白。在2,3 - 二磷酸甘油酸耗竭后，乳酸效应甚至增强。因此，我们认为在脱氧血红蛋白的β - 珠蛋白链的NH2末端缬氨酸处，二氧化碳和乳酸离子之间存在竞争。
