The Influence of Some Compounds Commonly Used in Biochemical Studies of Mitochondria on the Activity of Monoamine Oxidases

M. A. Zemskova,¹ L. N. Axenova,¹ and A. E. Medvedev^1,2

¹Institute of Biomedical Chemistry, Russian Academy of Medical Sciences, Pogodinskaya ul. 10, Moscow, 119832 Russia; fax: (7-095) 245-08-57.

²To whom correspondence should be addressed.

Submitted December 25, 1996.

It was previously described that low concentrations of sodium azide inhibit monoamine oxidase (MAO) B assayed by spectrophotometric measurement of benzaldehyde or by hydrogen peroxide accumulation. We failed to confirm this effect using radiometric determination of MAO activity. Tris or dinitrophenol inhibit MAO. The data suggest that some "regulatory effects" depend on the assay of MAO activity.

KEY WORDS: monoamine oxidase, Tris, dinitrophenol, azide.

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