title: Ontogenesis of multiple forms of monoamine oxidase in rat brain regions and liver.
abstract: The postnatal development of total, type-A and type-B monoamine oxidase (MAO) in the brain stem, forebrain and cerebellum, determined with preferred substrates or selective inhibitors, were found to follow different patterns. In the brain regions, MAO-A activity reached adult levels in the brain stem first, followed by the forebrain and cerebellum, while MAO-B reached adult levels in these regions at about the same time and later in postnatal life. On the other hand, both MAO-A and B activities were almost fully developed in the newborn liver. Moreover, total and type-A, but not type-B, showed a caudal-to-rostral sequence of biochemical maturation in the brain. The spatiotemporal pattern of differentiation of type-A and type-B activities in the brain tends to support the classification of brain MAO into two distinct isoenzymic forms.
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000254:growth & development / Q000378:metabolism; D001921:Brain / Q000201:enzymology* / Q000254:growth & development; D007527:Isoenzymes / Q000378:metabolism; D008099:Liver / Q000201:enzymology*; D008995:Monoamine Oxidase / Q000096:biosynthesis* / Q000145:classification / Q000378:metabolism; D008996:Monoamine Oxidase Inhibitors; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin; D014018:Tissue Distribution
chemical_list: D007527:Isoenzymes; D008996:Monoamine Oxidase Inhibitors; D012701:Serotonin; D008995:Monoamine Oxidase