Effect of Nitrous Oxide on Folate and Vitamin B12 Metabolism in Patients

@article{Koblin1990EffectON,
  title={Effect of Nitrous Oxide on Folate and Vitamin B12 Metabolism in Patients},
  author={Donald D. Koblin and Barbara W. Tomerson and Frederic M. Waldman and George H. Lampe and Linda Z. Wauk and Edmond I. Eger},
  journal={Anesthesia \& Analgesia},
  year={1990},
  volume={71},
  pages={610–617}
}
Exposure to nitrous oxide (N2O) markedly enhances excretion of formic acid and formiminoglutamic acid (FIGLU) in the urine of rats, suggesting a disruption in the normal pathways of folic acid metabolism secondary to an N2O-induced inactivation of methionine synthase. We tested whether surgical patients (23 having total hip replacements and 26 having resection of acoustic neuromas) exposed to isoflurane alone or combined with N2O responded similarly. We found no increase in urinary formic acid… Expand
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Toxicity of nitrous oxide.
  • J. Weimann
  • Medicine
  • Best practice & research. Clinical anaesthesiology
  • 2003
Nitrous oxide interacts with vitamin B12 resulting in selective inhibition of methionine synthase, a key enzyme in methionine and folate metabolism. Thus, nitrous oxide may alter one-carbon and… Expand
Aging, chronic administration of ethanol, and acute exposure to nitrous oxide: Effects on vitamin B12 and folate status in rats
TLDR
In this animal model, aging, chronic ethanol administration, and acute N2O exposure did not act synergistically to produce prolonged and severe disturbances in folate and vitamin B12 metabolism. Expand
Biologic Effects of Nitrous Oxide A Mechanistic and Toxicologic Review
Nitrous oxide is the longest serving member of the anesthesiologist’s pharmacologic armamentarium but remains a source of controversy because of fears over its adverse effects. Recently, the… Expand
Biologic Effects of Nitrous Oxide: A Mechanistic and Toxicologic Review
TLDR
Although it would seem prudent to avoid nitrous oxide in certain vulnerable populations, current evidence in support of a more widespread proscription from clinical practice is unconvincing. Expand
Study of Methylene Tetrahydrofolate Reductase (MTHFR) Gene Polymorphisms in Personnel Prolonged Exposure to Trace Quantities of Anaesthetic Gases in Operation Theatres
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Evaluated prevalence of MTHR C677T and A 1298C mutation in Operation Theatre exposed personnel and compared with Non OT exposed healthy controls indicated statistically significant difference in prevalence in sex wise distribution in OT exposed personnel. Expand
General anesthetics and therapeutic gases
Publisher Summary This chapter discusses several general anesthetics and therapeutic gases and their adverse effects. Enflurane is a known cerebral irritant with an ability to cause convulsions, but… Expand
Drugs as anti-nutrients
TLDR
Many drugs have been identified, which appear to cause deficiencies in essential nutrients and their metabolites, and nutrients could be prescribed with drugs, to limit the damage done, provided that this does not undermine the action of the drugs. Expand
Exploring Nitrous Oxide as Treatment of Mood Disorders: Basic Concepts.
TLDR
The goal of this brief review was to educate psychiatrists about the basic concepts of nitrous oxide administration and pharmacology. Expand
A review of physiological and metabolic effects of essential amino acids
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Ten essential amino acids are reviewed with regard to their metabolic, physiologic and therapeutic effects throughout the human body and their diverse roles in special nitrogen containing products, neurotransmitters, and as alternative energy sources. Expand
Adverse Effects of General Anaesthetics
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Evidence points to 2 distinct syndromes; direct toxicity from the Products of reductive metabolism, and a more serious illness, immunologically mediated via haptens formed by liver proteins and the products of oxidative metabolism. Expand
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References

SHOWING 1-10 OF 29 REFERENCES
Effect of nitrous oxide on serum vitamin-B12 levels under surgical anesthesia.
TLDR
It is suggested that the effect of nitrous oxide as used in surgical anesthesia may be considered insignificant in patients with normal vitamin-B12 values. Expand
Urinary folate loss following inactivation of vitamin B12 by nitrous oxide in rats
TLDR
It was concluded that the folate deficiency that develops in the N2O‐treated rat is due to massive urinary loss of folate which appears to be secondary to impaired cellular uptake of folates which leads to a raised plasma folate level. Expand
Increased urinary excretion of formiminoglutamic acid in nitrous-oxide-treated rats and its reduction by methionine.
TLDR
There is a marked increase in the excretion of formiminoglutamic acid in the urine following exposure to nitrous oxide and a significant decrease is produced, while on N2O, by giving methionine. Expand
Clinical aspects of the interaction between nitrous oxide and vitamin B12.
  • J. Nunn
  • Medicine
  • British journal of anaesthesia
  • 1987
TLDR
There was thus a parallel with megaloblastic anaemia and a working hypothesis for the agranulocytosis and the teratogenesis which had previously been observed as toxic effects of nitrous oxide. Expand
Nitrous Oxide Inactivates Methionine Synthetase in Human Liver
TLDR
Results in humans are similar to those in animals and suggest that inactivation of methionine synthetase may play a role in the development of the pathologic effects seen in patients and medical personnel after exposure to nitrous oxide. Expand
Studies on the haemopoietic toxicity of nitrous oxide in man
TLDR
Megalo‐blastosis was associated with abnormal dU suppression which showed a correction pattern similar to that seen in vitamin Bi2 deficiency and Administration of N20 was also associated with a progressive rise in serum folate and fall in serum methionine levels. Expand
MEGALOBLASTIC HÆMOPOIESIS IN PATIENTS RECEIVING NITROUS OXIDE
TLDR
It is suggested that nitrous oxide interferes with the function of vitamin B12 in vitro and probably also in vivo when premixed 50% Nitrous oxide and 50% oxygen mixture ('Entonox') is given. Expand
Conversion of endogenous cobalamins into microbiologically‐inactive cobalamin analogues in rats by exposure to nitrous oxide
TLDR
It was concluded that microbiologically‐inactive cobalamines are produced in vivo from endogenous cobalamins and that one form appears to be a product of cobalamin oxidation. Expand
Clinical Pharmacology of Nitrous Oxide: An Argument for Its Continued Use
TLDR
The addition of N2O administration decreased the isoflurane requirement for clinical anesthesia but did not alter most of the clinical variables measured in practice, including blood pressure, heart rate, rate of recovery from anesthesia, development of postoperative pain, patient satisfaction with anesthesia, or duration of anesthesia or of hospitalization. Expand
Dimethylthiourea, a hydroxyl radical scavenger, impedes the inactivation of methionine synthase by nitrous oxide in mice.
TLDR
The findings are consistent with the hypothesis that nitrous oxide combines with the vitamin B12 molecule of methionine synthase to form a hydroxyl radical that reacts with an inactivates the enzyme, and that DMTU slows this inactivation by scavengingHydroxyl radicals. Expand
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