Effect of pH, Temperature, and 2–3 DPG
on the O2-Hb Dissociation Curve
• pH
– Decreased pH lowers Hb-O2 affinity
– Results in a “rightward” shift of the curve
Favors “offloading” of O2 to the tissues
• Temperature
– Increased blood temperature lowers Hb-O2 affinity
– Results in a “rightward” shift of the curve
• 2–3 DPG
– Byproduct of RBC glycolysis
– May result in a “rightward” shift of the curve
During altitude exposure
Not a major cause of rightward shift during exercise