title: Effects of zinc ion on type A monoamine oxidase in monkey brain mitochondria.
abstract: The effects of ZnSO(4) on types A and B monoamine oxidase (MAO) isozymes in monkey brain mitochondria were investigated, in vitro. Type A MAO activity in monkey brain decreased to about 50% with 1 microM ZnSO(4) using serotonin as a substrate, and this inhibition was proportional to the concentration of ZnSO(4). ZnSO(4) had no effect, however, on type B MAO activity in monkey brain using beta-phenylethylamine as a substrate. The inhibition by ZnSO(4) of type A MAO activity was competitive and reversible. ZnSO(4) did not inhibit either type A or type B MAO activity in rat brain mitochondria. Almost similar results were also obtained when ZnCl(2) was used, in vitro. These results indicate that the inhibiting action of zinc ion differs depending on animal species and organ. Type A MAO in monkey brain mitochondria was highly sensitive to zinc ion, while type B activity was less sensitive.
authors.affiliation: Department of Pharmacology, Oita Medical University, 1-1 Idaigaoka, Hasama-machi, Oita 879-5593, Japan. egacy@oita-med.ac.jp
authors.forename: Toru
authors.initials: T
authors.lastname: Egashira
authors.forename: Fusako
authors.initials: F
authors.lastname: Takayama
authors.forename: Kumiko
authors.initials: K
authors.lastname: Sakai
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000166:cytology*; D008251:Macaca; D008297:Male; D008928:Mitochondria / Q000187:drug effects* / Q000201:enzymology; D008995:Monoamine Oxidase / Q000378:metabolism*; D015032:Zinc / Q000494:pharmacology*
chemical_list: D008995:Monoamine Oxidase; D015032:Zinc