Monoamine oxidases: old friends hold many surprises

Abstract

The two forms of monoamine oxidase (MAO), A and B, continue to be of major interest to biochemists, pharmacologists, neurologists, and gerontologists. Despite intensive study for more than half a century, unexpected and unique properties of these enzymes continue to come to light. Recent studies have centered on their kinetic mechanism, their unique predilection for substrates related to the neurotoxic tertiary amine MPTP, and their putative role in aging and in the etiology of neurodegenerative diseases. New and potent inhibitors of MAO A and MAO B continue to be developed because of their potential use in clinical medicine. Some are effective in the picomolar range but MAO B from different mammalian species shows remarkable differences in sensitivity to these agents.

Biochemical and Physiological Processes in Brain Function and Drug Actions

“…In the case of the biogenic amines, while reuptake is the major means of limiting their synaptic activity, significant contributions to inactivation are made via the enzymes catechol-O-methyl transferase (Guldberg and Mardsen 1975;Mannisto et al 1992) and monoamine oxidase (Singer and Ramsay 1995). Inactivation by these enzymes does not result in any known reusable or physiologically active products.…”

Pet Imaging Studies in Drug Abuse Research

“…Monoamine oxidase occurs in most cells in most species (Singer et al, 1995). It is , located in the outer mitochondrial membrane and oxidizes amines from both endogenous and exogenous sources.…”

“…Monoamine oxidase occurs in most cells in most species (Singer et al, 1995). It is , It has been known for many years that platelet MAO is significantly lower in smokers (Oreland et al, 1981).…”

“…However, tobacco smoke -contains several thousand chemical compounds and some of these may also contribute to some of its pharmacological effects. Our studies have focussed on the effect of tobacco smoke exposure on the enzyme monoamine oxidase (MAO).Monoamine oxidase occurs in most cells in most species (Singer et al, 1995). It is , located in the outer mitochondrial membrane and oxidizes amines from both endogenous and exogenous sources.…”

Efficient synthesis of [11C]befloxatone, a selective radioligand for the in vivo imaging of MAO‐A density using PET

“…1 Two isoforms of MAO have been described, MAO-A and MAO-B. They differ by their substrate selectivity and by their inhibitor sensitivity [2][3][4][5][6][7][8] and are both important for neurotransmitter regulation.…”