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Oxidation of 5-methyltetrahydrofolate in cobalamin-inactivated rats.

ABSTRACT: Rats were exposed to nitrous oxide, which inactivates cob(I)alamin (Cbl). As in air-breathing rats methionine administration led to the conversion of hepatic 5-methyltetrahydrofolate (MeH4 folate) into formyltetrahydrofolate. The recovery of MeH4 folate levels in liver after its oxidation initiated by methionine was noted and the rate compared with that for air-breathing rats. Oxidation of MeH4 folate was less complete and occurred more slowly in Cbl-inactivated rats as compared with controls. However, recovery of MeH4 folate levels was more rapid in Cbl inactivation. S-Adenosylmethionine did not produce a significant change in MeH4 folate levels in Cbl-inactivated rats, whereas it did so in air-breathing animals.

SUBMITTER: Lumb M

PROVIDER: S-EPMC1138450 | biostudies-other | 1989 Mar

REPOSITORIES: biostudies-other

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Folate polyglutamate synthetase activity in the cobalamin-inactivated rat.

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2022-08-05 | GSE203302 | GEO

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