Journal of Applied Physiology, Vol 57, Issue 2 429-434, Copyright © 1984 by American Physiological Society
Human whole-blood oxygen affinity: effect of temperature
A. Zwart, G. Kwant, B. Oeseburg and W. G. Zijlstra
phe effect of temperature changes on human whole-blood O2 affinity was
measured in the blood of six healthy donors over almost the entire O2
saturation (SO2) range (1-99%). The results showed that temperature has no
influence on the shape of the O2 dissociation curve, implying that the
temperature coefficient (delta log PO2/delta T) is independent of SO2.
Simultaneous measurements of the total (proton) Haldane factor
(delta[HbH]/[delta HbO2]) at the five temperatures under study (22, 27, 32,
37, and 42 degrees C) revealed that this factor depends on temperature. The
liberation of protons from hemoglobin appeared to be linear with respect to
changes in SO2. We therefore conclude that the (proton) Bohr factor (H+
factor) is dependent on temperature over the entire SO2 range in the same
way as previously described for SO2 = 50%. The exothermic oxygenation
reaction in whole blood was accompanied by a heat evolution (delta HO2) of
42.7 kJ/mol (monomeric) hemoglobin.
