Brain monoamine oxidase and replacement of its coenzyme flavin in rats.
The influence of 7-ethyl-8-methylflavin and 7-methyl-8-ethylflavin, vitamin-like homologues of riboflavin, on rat brain mitochondrial monoamine oxidase (MAO) was studied using tyramine as substrate. While riboflavin deficiency caused the enzyme activity to fall to 80% of norma, when 7-ethyl-8-methylflavin replaced riboflavin as the precursor of its coenzyme, it caused essentially complete loss of the enzyme activity. We showed that while 7-ethyl-8-methylflavin can serve as a coenzyme for MAO, 7-methyl-8-ethylflavin cannot serve as coenzyme for this enzyme.
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000201:enzymology*; D003067:Coenzymes / Q000494:pharmacology; D005260:Female; D007700:Kinetics; D008928:Mitochondria / Q000201:enzymology; D008995:Monoamine Oxidase / Q000378:metabolism*; D051381:Rats; D012256:Riboflavin / Q000031:analogs & derivatives* / Q000494:pharmacology; D012257:Riboflavin Deficiency / Q000201:enzymology; D014439:Tyramine / Q000378:metabolism
C016440:7-ethyl-8-methylflavin; D003067:Coenzymes; C016576:7-methyl-8-ethylflavin; D008995:Monoamine Oxidase; D012256:Riboflavin; D014439:Tyramine