Which volatile anesthetic is associated with the inhibition of vitamin B12 dependent enzymes?

Nitrous oxide is associated with the inhibition of vitamin B12 dependent enzymes, primarily because it can inactivate vitamin B12, which is crucial for certain enzymatic reactions in the body. Specifically, nitrous oxide affects methionine synthase, an enzyme that relies on vitamin B12 to function properly. This inhibition can lead to a range of metabolic disturbances, particularly in the case of prolonged exposure to the anesthetic.

In contrast, the other volatile anesthetics listed do not have the same effect on vitamin B12 dependent enzymes. Isoflurane, desflurane, and sevoflurane are inhaled anesthetics that primarily work by modulating GABA receptors and other brain pathways. They do not show the same capacity to interfere with vitamin B12 metabolism. Understanding the unique interaction of nitrous oxide with vitamin B12 is crucial for recognizing potential risks associated with its use, especially in patients who may have pre-existing deficiencies or long-term exposure during surgeries.