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Updated: Sep 13, 2026

Methods to Identify the NMR Resonances of the 13C-Dimethyl N-terminal Amine on Reductively Methylated Proteins
13:59

Methods to Identify the NMR Resonances of the 13C-Dimethyl N-terminal Amine on Reductively Methylated Proteins

Published on: December 12, 2013

The enzymatic systems involved in the mammalian metabolism of methylamine

M S Dar, P L Morselli, E R Bowman

    General Pharmacology
    |January 1, 1985
    PubMed

    Insights

    This study investigated methylamine metabolism in rats, finding that iproniazid

    Area of Science:

    • Biochemistry
    • Pharmacology
    • Microbiology

    Background:

    • Methylamine is a biologically relevant compound.
    • Monoamine oxidase (MAO) and intestinal bacteria are potential pathways for methylamine metabolism.

    Purpose of the Study:

    • To investigate the role of MAO and intestinal bacteria in rat methylamine metabolism.
    • To determine if MAO is the primary enzyme system involved in methylamine oxidation.

    Main Methods:

    • Rats were administered methyl-[14C]amine hydrochloride.
    • Short- and long-acting MAO inhibitors were administered.
    • Radioactivity in expired air and urine was measured.

    Main Results:

    • Iproniazid's inhibitory effect on methylamine oxidation is mediated by systems separate from MAO.
    • MAO is not the primary contributor to methylamine metabolism as previously suggested.
    • Intestinal bacterial oxidation plays a minor role in overall methylamine metabolism.

    Conclusions:

    • Methylamine metabolism involves enzyme systems distinct from MAO.
    • The role of MAO in methylamine metabolism is less significant than previously thought.
    • Intestinal bacteria contribute minimally to methylamine breakdown.

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