Noradrenaline-degrading activity of monoamine oxidase is localized in noradrenergic neurons of the locus coeruleus of the rat.
We found intense monoamine oxidase (MAO) activity in rat locus coeruleus (LC) neurons by means of a histochemical method using noradrenaline as a substrate. This MAO activity was abolished by clorgyline, a specific inhibitor of MAO type A. Fluorescence immunohistochemistry for tyrosine hydroxylase (TH) combined with MAO histochemistry revealed intense MAO activity in virtually all TH-immunoreactive LC neurons (i.e. noradrenergic neurons). The results indicate that noradrenaline produced in LC neurons might be degraded by MAO type A activity.
D000818:Animals; D003010:Clorgyline / Q000494:pharmacology; D005455:Fluorescent Antibody Technique; D006651:Histocytochemistry; D008125:Locus Coeruleus / Q000166:cytology / Q000378:metabolism*; D008297:Male; D008995:Monoamine Oxidase / Q000378:metabolism*; D008996:Monoamine Oxidase Inhibitors / Q000494:pharmacology; D009474:Neurons / Q000378:metabolism*; D009638:Norepinephrine / Q000037:antagonists & inhibitors / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014018:Tissue Distribution / Q000502:physiology; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism