Inhibition of monoamine oxidase modulates the behaviour of semicarbazide-sensitive amine oxidase (SSAO).
The specific activity and kinetic behaviour of semicarbazide-sensitive amine oxidase (EC 1.4.3.6; SSAO) towards benzylamine, in the rat heart, is affected by in vivo treatment with the non-selective monoamine oxidase (MAO) inhibitor tranylcypromine, but not by the selective MAO-A and -B inhibitors, clorgyline and lazabemide. SSAO activity was increased to 178% of control activity after 7 days of treatment with tranylcypromine. This increase appears to represent an increase in the limiting velocity (V(max)) for benzylamine oxidation with no significant change in the K(m) at that time-point. However, the K(m) for benzylamine oxidation was found to decrease in both controls and treated groups, in a time-dependent manner, during the treatment regime. These findings suggest a link between SSAO and cellular stress and may have importance in the context of the recent finding that tissue-SSAO is identical to a vascular adhesion protein (VAP1), involved in the process of inflammation.
Fitzgerald
D H
DH
School of Dentistry, Trinity College, Dublin, Ireland.
Tipton
K F
KF
D006631:Amine Oxidase (Copper-Containing) / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000201:enzymology*; D003010:Clorgyline / Q000494:pharmacology; D004298:Dopamine / Q000378:metabolism; D005260:Female; D006321:Heart / Q000187:drug effects / Q000502:physiology*; D007700:Kinetics; D008099:Liver / Q000187:drug effects / Q000201:enzymology*; D008995:Monoamine Oxidase / Q000187:drug effects / Q000378:metabolism*; D008996:Monoamine Oxidase Inhibitors / Q000494:pharmacology*; D009206:Myocardium / Q000201:enzymology*; D010848:Picolinic Acids / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000378:metabolism; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism; D014191:Tranylcypromine / Q000494:pharmacology
D008996:Monoamine Oxidase Inhibitors; D010848:Picolinic Acids; D012701:Serotonin; D014191:Tranylcypromine; C059303:lazabemide; D006631:Amine Oxidase (Copper-Containing); D008995:Monoamine Oxidase; D003010:Clorgyline; D004298:Dopamine