Methods for assaying monoamine oxidase A and B activities: recent developments.

MAO A and MAO B are mitochondrial enzymes responsible for the oxidative dea mination of monoaminergic neurotransmitters and exogenous monoamines. They thus play an important physiological role in the central nervous system and peripheral organs, and numerous laboratories perform measurements of the a ctivity of the two enzymes both for basic research and for clinical and pha rmacological studies. Several methods are available for monitoring MAO acti vity, including radiometric, fluorometric, spectrophotometric, polarographi c, chromatographic and luminometric assays. The advantages and drawbacks of many of these methods have been exhaustively described in previous reviews to which reference may be made (Tipton and Youdim, 1983; Nicotra and Parve z, 1998). The present review deals in particular with recent developments i n this field and describes several of the mon significant methods published in the literature in the '90s. For each method, in addition to the underly ing principle, the short protocols, applications and any limitations an des cribed.