Yamaguchi K, Glahn J, Scheid P, Piiper J
Respir Physiol. 1987 Feb;67(2):209-23. doi: 10.1016/0034-5687(87)90042-9.
The influence of temperature (varied from 37 to 7 degrees C) and of medium pH (varied from 7.7 to 7.1) on the kinetics of O2 uptake and release by human red blood cells (RBC) under stopped-flow conditions was investigated by double-beam spectrophotometry. From the rate of O2 saturation change and the mean effective PO2 difference between the medium and the Hb of RBC, the specific transfer conductance for O2, G, was calculated. The temperature coefficient, Q10, of G for O2 uptake averaged 1.17, activation energy, Ea, 2.6 kcal/mol O2; the average values for O2 release were: Q10 = 1.32, Ea = 4.8 kcal/mol O2. The G value for release of O2 from oxyhemoglobin solution, Gsol, yielded Q10 = 2.25, Ea = 13.5 kcal/mol O2. Comparison of these Q10 and Ea values with those for diffusion of O2 and hemoglobin in aqueous media leads to the conclusion that in the stopped-flow condition the conductance for O2 transfer was mainly limited by diffusion of O2 and hemoglobin in the red cell interior and by diffusion of O2 in the medium, and to a lesser degree by chemical reaction kinetics. This was further supported by the lack of dependence of O2 transfer conductance values on pH.
采用双光束分光光度法研究了温度（从37℃变化至7℃）和介质pH值（从7.7变化至7.1）对人红细胞（RBC）在停流条件下摄取和释放O₂动力学的影响。根据O₂饱和度变化率以及介质与红细胞血红蛋白之间的平均有效PO₂差值，计算出O₂的比转移传导率G。摄取O₂时G的温度系数Q₁₀平均为1.17，活化能Ea为2.6千卡/摩尔O₂；释放O₂时的平均值为：Q₁₀ = 1.32，Ea = 4.8千卡/摩尔O₂。从氧合血红蛋白溶液中释放O₂的G值Gsol，其Q₁₀ = 2.25，Ea = 13.5千卡/摩尔O₂。将这些Q₁₀和Ea值与O₂和血红蛋白在水性介质中的扩散值进行比较，得出结论：在停流条件下，O₂转移的传导率主要受O₂和血红蛋白在红细胞内部的扩散以及O₂在介质中的扩散限制，在较小程度上受化学反应动力学限制。O₂转移传导率值对pH的不依赖性进一步支持了这一点。
