[Skip to Content]
Access to paid content on this site is currently suspended due to excessive activity being detected from your IP address Please contact the publisher to request reinstatement.
[Skip to Content Landing]
November 1976

Platelet Monamine Oxidase in SchizophreniaAn Investigation in Drug-Free Chronic Hospitalized Patients

Author Affiliations

From the Division of Psychiatry (Drs Owen, Bourne, Crow, and Johnstone), Clinical Research Centre, Harrow, Middlesex, British United Provident Association Medical Centre Research Department (Dr Bailey), King's Cross, London, and Shenley Hospital (Dr Hershon), Radlett, Hertfordshire, England.

Arch Gen Psychiatry. 1976;33(11):1370-1373. doi:10.1001/archpsyc.1976.01770110098010

• Platelet monoamine oxidase (MAO) activity was investigated in a series of 60 patients with chronic schizophrenic illnesses free from neuroleptic medication, and 70 normal controls. No significant differences in platelet MAO activity or in substrate preference were detected between patients and controls, using tryptamine and tyramine as substrates. Platelet MAO activity did not distinguish patients with positive symptoms from those with negative symptoms alone and did not show any relationship with severity of disease or with a number of clinical features. These findings suggest that low platelet MAO activity cannot be regarded as a genetic marker for schizophrenia. Important determinants of platelet MAO activity yet to be discovered may have contributed to the discrepancies in recent observations of platelet MAO activity in schizophrenia.