What effect does 2,3-DPG have on the oxygen dissociation curve?

2,3-DPG, or 2,3-diphosphoglycerate, plays a significant role in oxygen transport and delivery by influencing the hemoglobin-oxygen binding affinity. When 2,3-DPG binds to hemoglobin, it stabilizes the deoxygenated form of hemoglobin, causing a decrease in hemoglobin’s affinity for oxygen. This stabilization leads to a rightward shift in the oxygen dissociation curve.

A rightward shift means that at any given partial pressure of oxygen (PaO2), hemoglobin will release more oxygen to the tissues. This mechanism is particularly beneficial during conditions of high metabolic demand, such as exercise or in states of hypoxia, where tissues require more oxygen.

Therefore, the correct understanding is that 2,3-DPG enhances the ability of tissues to extract oxygen from the blood by promoting the release of oxygen from hemoglobin, which aligns with the idea that it facilitates increased oxygen delivery to those tissues in need.