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Updated: Aug 11, 2026

Mouse Adrenal Chromaffin Cell Isolation
Published on: January 5, 2007
Mechanism-based inactivation of dopamine beta-monooxygenase in adrenal chromaffin cells
S W May1, F K Young, J L Powers
1School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta 30332, USA. sheldon.may@chemistry.gatech.edu
Abstract:
Dopamine beta-monoxygenase (DBM, E.C. 1.14.17.1) is an attractive target point for possible modulation of adrenergic activity, and a variety of DBM-targeted pseudosubstrates and inhibitors have been developed in this laboratory and other laboratories. We now demonstrate the efficacy of a DBM-targeted mechanism-based inactivator, as well as enzymatic processing of two alternate DBM substrates, within functional adrenal chromaffin cells. When cultured adrenal medullary chromaffin cells were incubated with the mechanism-based inactivator 1-(4'-hydroxyphenyl)-1-(aminomethyl)-ethene (HOPAME), vesicular DBM activity was markedly decreased. Similarly, the alternate substrates 4'-hydroxyphenyl-2-aminoethyl sulfide and 4'-hydroxyphenyl-2-aminopropyl selenide each undergo uptake and DBM-catalyzed oxygenation within these cells. The simultaneous action of both the mechanism-based inactivator and an alternate substrate within functional chromaffin cells was also demonstrated. These results provide support for a direct mechanistic link between the enzymological properties of DBM-targeted adrenergic agents and their in-vivo pharmacological activities.
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