[Defect in the properties of brain mitochondrial monoamine oxidase in schizophrenia].
A highly purified individual form of monoamine oxidase (MAO-11b) has been isolated by means of affinity chromatography on AH-Sepharose 4B after solubilization of biomembranes from schizophrenic or normal brain tissues. The enzyme preparations obtained catalyzed deamination (both in schizophrenia and normal state) not only of serotonin and 2-phenylethylamine but also of histamine and contained about 2 SH-groups per 10(5) dalton of protein which is characteristic for "transformed" MAO with partially oxidized SH-groups. Preincubation of MAO-11b from normal brain with 10 mM dithiothreitol caused "re-transformation" of MAO: there was a marked decrease in histamine deaminating activity with simultaneous increase in the MAO activity and in content of SH-groups. In schizophrenia the re-transformation of MAO was impaired: preincubation of MAO-11b under the same conditions led to an increase in content of SH-groups and in MAO activity but the preincubation with a reducing agent did not decrease (causing, to the contrary, a marked increase) the deamination of histamine.
D001921:Brain / Q000201:enzymology*; D003641:Deamination; D006801:Humans; D008928:Mitochondria / Q000201:enzymology*; D008995:Monoamine Oxidase / Q000378:metabolism*; D012559:Schizophrenia / Q000201:enzymology*; D013379:Substrate Specificity
D008995:Monoamine Oxidase
O narusheniiakh svoĭstv mitokhondrial'noĭ monoaminoksidazy mozga pri shizofrenii.