Medicipate! Conserve your knowledge 
Medicipate!
Conserve your knowledge
 
Write article
Please log in to edit this article.

2,3-Bisphosphoglyceric acid

Synonyms: 2,3-bisphosphoglycerate, 2,3-diphosphoglyceric acid, 2,3-BPG
German: 2,3-Diphosphoglycerat

1 Definition

2,3-Bisphosphoglyceric acid, 2,3-BPG for short, is an important regulator for the binding affinity of oxygen to hemoglobin, along with other regulators like pH and oxygen partial pressure.

2 Chemistry

2,3-Bisphosphoglyceric acid is formed in red blood cells through the Luebering-Rapoport pathway (a byway of glycolysis) from accumulating 1,3-Bisphosphoglyceric acid. The reaction is catalyzed by 2,3-Bisphosphoglycerate mutase. 2,3-DPG binds through a non-covalent bond to the beta-subunit of deoxyhemoglobin, but does not bind to oxygenated hemoglobin.

3 Physiology

2,3-Bisphosphoglyceric acid lowers the oxygen affinity of hemoglobin by stabilizing its T form ("tense"). This facilitates the release of oxygen to tissues, while impeding oxygen uptake in the pulmonary circulation at the same time. As a result, the oxygen–hemoglobin dissociation curve is shifted to to the right through the influence of 2,3-BPG.

3.1 Influencing factors

  • The concentration of 2,3-BPG adjusts to external conditions. At high altitudes, for instance, the concentration increases. The increase in 2,3-BPG leads to an increased production of red blood cells, mediated by the hormone erythropoietin.
  • A drop in pH also results in a low concentration of 2,3-BPG in erythrocytes, as acidosis inhibits glycolysis.
  • Physical exertion, thyroid hormones and androgens stimulate the production of 2,3-BPG
  • During the course of anemia, the rate of 2,3-BPG production increases as well, in order to improve oxygen supply.

During pregnancy, the increase in 2,3-BPG allows increased delivery of oxygen to the fetus. Instead of two beta polypeptide chains, fetal hemoglobin (HbF) contains two gamma polypeptide chains, which are unable to bind 2,3-BPG. Accordingly, 2,3-BPG only affects maternal hemoglobin and not that of the fetus.

Cave: 2,3-BGP disintegrates even when it is stored in blood bags at low temperatures.

4 References

To comment on this article, .

Click here for creating a new article in the DocCheck Flexikon.

Initial author:

0 rating(s) (0 ø)
Share

5 Views

You have any questions?
Language:
Follow DocCheck: