Summary
Intra- and extraneuronal compartments of rat hearts were selectively labelled by perfusion with 3H-noradrenaline in the presence of corticosterone 87 μM or cocaine 30 μM, respectively. The subsequent outflow of 3H-compounds was examined. As little as 1 nM amezinium diminished the outflow of intraneuronally formed 3H-DOPEG. This effect was antagonized by cocaine. Amezinium 1 μM was necessary to diminish the outflow of extraneuronally formed 3H-DOPEG. This effect was not counteracted by corticosterone. The results indicate that amezinium is both a potent and, at low concentrations, selective inhibitor of intraneuronal MAO.
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Abbreviations
- DOMA:
-
3,4-dihydroxymandelic acid
- DOPEG:
-
3,4-dihydroxyphenylglycol
- MAO:
-
monoamine oxidase (EC 1.4.3.4)
- NA:
-
noradrenaline
- NMN:
-
normetanephrine
- OMDA:
-
O-methylated deaminated metabolites
References
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Steppeler, A., Starke, K. Selective inhibition by amezinium of intraneuronal monoamine oxidase. Naunyn-Schmiedeberg's Arch. Pharmacol. 314, 13–16 (1980). https://doi.org/10.1007/BF00498426
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DOI: https://doi.org/10.1007/BF00498426