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Reduction of blood platelet monoamine oxidase activity in schizophrenic patients on phenothiazines

S Takahashi, H Yamane, N Tani

    Folia Psychiatrica Et Neurologica Japonica
    |January 1, 1975
    PubMed

    Insights

    Blood platelet monoamine oxidase (MAO) activity was measured in schizophrenic patients. Untreated patients showed no significant MAO reduction, suggesting MAO levels are not linked to schizophrenia diagnosis.

    Area of Science:

    • Neuroscience
    • Biochemistry

    Background:

    • Monoamine oxidase (MAO) plays a crucial role in neurotransmitter metabolism.
    • Altered MAO activity has been implicated in various psychiatric disorders.

    Purpose of the Study:

    • To investigate blood platelet monoamine oxidase (MAO) activity in schizophrenic patients.
    • To determine if MAO activity is associated with schizophrenia diagnosis or treatment.

    Main Methods:

    • A newly developed assay was used to measure MAO activity in blood platelets using serotonin as a substrate.
    • MAO activity was assessed in 76 schizophrenic patients (33 untreated) and compared to normal controls.

    Main Results:

    • No significant reduction in blood platelet MAO activity was observed in untreated schizophrenic patients compared to controls.
    • Male schizophrenic patients exhibited lower MAO activity than females, consistent with findings in normal subjects.
    • Phenothiazine treatment significantly reduced platelet MAO activity, without affecting platelet serotonin content or count.

    Conclusions:

    • Blood platelet MAO activity does not appear to be directly related to the psychiatric diagnosis of schizophrenia.
    • MAO activity may be influenced by hormonal factors rather than a predisposition to schizophrenia.
    • Phenothiazine treatment impacts MAO activity, highlighting a potential therapeutic mechanism.

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