Effect of Sulfhydryl Inhibition on the Rate of the Red Blood Cell O₂- Uptake

Abstract

1) The over-all association velocity constant (Kc) for the combination of oxygen with human red blood cell suspensions at 0% initial saturation have been measured in a consinuous flow rapid reaction apparatus with oxygen electrode.
2) Kc of 13 normal control measurement were in between 110 and 215 mM^-1 sec^-1, and mean ±S. D. was 144.5±25.9 mM^-1 sec^-1. These values were in good agreement with previously reported values. Repeated measurement of two identical cases showed approximately close value.
3) Because of relatively large variation of individual Kc value, caution should be paid to use it for calculation or simulation of pulmonary oxygen uptake process.
4) Kc after alteration of chemical constituents of the red blood cell membrane have been measured as a new approach to investigate whether red blood cell membrane is a barrier to oxygen diffusion.
5) Sulfhydryl residues were inhibited by irradiation and treatment with mercurials. The Kc of treated red blood cells were not different from control. This result suggests that the sulfhydryl inhibition has not a significant effect on the rate of the red blood cell O₂ uptake.