[Various mammalian tissues contain cell membrane-bound amine oxidase termed semicarbazide-sensitive amine oxidase (SSAO, EC 1.4.3.6)].

Recently it has been demonstrated a role of fat-cell SSAO on glucose transport and GLUT4 translocation to the cell surface. Many compounds have been identified as relatively selective SSAO inhibitors, but those currently available also inhibit monoamine oxidase (MAO, EC 1.4.3.4). In this study, inhibitory properties of a haloamine, 2-bromoethylamine (2-BEA), to guinea pig and rat lung-bound SSAO have been studied. 2-BEA could not inhibit both forms of MAO, but it competitively inhibited rat lung SSAO activity with a Ki value of 2.5 microM without preincubation and after preincubation, the mode of inhibition changed to be non-competitive. Dialysis and dilution experiments with 2-BEA-pretreated preparations resulted in no recovery of SSAO activity. A decreased rate of SSAO inhibition under N2 atmosphere to that obtained under O2 was produced after 2-BEA treatment, suggesting that oxidised intermediate was necessary for its inhibition. The plot of 1/k' vs 1/2-BEA intersected on the y-axis indicate that the inhibition by 2-BEA is not affinity-labeling agent, but a suicide inhibitor of SSAO.