O2Affinität

O2Affinität, also known as oxygen affinity, refers to the ability of a molecule, typically hemoglobin, to bind and transport oxygen. This is a crucial physiological process for the survival of aerobic organisms. Hemoglobin, found in red blood cells, is the primary molecule responsible for oxygen transport in the blood. Its affinity for oxygen can be influenced by several factors, including the partial pressure of oxygen, temperature, pH, and the concentration of 2,3-bisphosphoglycerate (2,3-BPG).

When the partial pressure of oxygen is high, such as in the lungs, hemoglobin readily binds oxygen, becoming saturated. As blood circulates to tissues where oxygen levels are lower, hemoglobin releases its bound oxygen. This release is facilitated by a decrease in oxygen partial pressure and an increase in factors like acidity and 2,3-BPG concentration, which lower hemoglobin's affinity for oxygen. This dynamic regulation ensures that oxygen is delivered efficiently to where it is needed most for cellular respiration.

Factors that increase oxygen affinity, such as higher pH (alkalosis) or lower levels of 2,3-BPG, cause the oxygen-hemoglobin dissociation curve to shift to the left. This means that hemoglobin holds onto oxygen more tightly, and less oxygen is released to the tissues. Conversely, factors that decrease oxygen affinity, such as lower pH (acidosis) or higher levels of 2,3-BPG, shift the curve to the right, promoting greater oxygen release. Understanding O2Affinität is vital in medicine, particularly in managing conditions affecting oxygen transport and delivery, such as anemia, lung diseases, and heart conditions.