Platelet Mao Activity and Evoked Potentials in the Identification of Subjects Biologically at Risk for Psychiatric Disorders

1979 ◽  
Vol 134 (4) ◽  
pp. 372-381 ◽  
Author(s):  
R. D. Coursey ◽  
M. S. Buchsbaum ◽  
D. L. Murphy
Keyword(s):  
At Risk ◽  
Psychiatric Disorders ◽  
High Risk Group ◽  
Activity Levels ◽  
Platelet Mao ◽  
Student Volunteers ◽  
Mao Activity ◽  
Platelet Mao Activity ◽  
Platelet Monoamine Oxidase ◽  
Males And Females

SummaryIndividuals potentially at risk for psychiatric disorders were identified by screening 375 college student volunteers for low platelet monoamine oxidase (MAO) activity levels. The lower and upper 10 per cent in MAO activity were administered a personal and family history interview, psychological tests and average evoked response (AER) electroencephalographic procedures. Results indicated that low MAO males and females were socially more active, had more psychiatric contact, and had relatives who were psychiatric-ally more disturbed than high MAO subjects. Low MAO males had more convictions, experimented more with illegal drugs and had elevated scores on the MMPI. AER criteria further defined a high risk group of low MAO-AER augmenters which had more suicides among their relatives and higher scores on the schizophrenia scale of the MMPI.

Toward a Biochemical Classification of Depressive Disorders IX

1985 ◽  
Vol 146 (6) ◽  
pp. 633-637 ◽  
Author(s):  
Alan F. Schatzberg ◽  
Anthony J. Rothschild ◽  
Benjamin Gerson ◽  
Jan E. Lerbinger ◽  
Joseph J. Schildkraut
Keyword(s):  
Depressive Disorders ◽  
Activity Levels ◽  
Platelet Mao ◽  
Mao Activity ◽  
Platelet Mao Activity ◽  
Platelet Monoamine Oxidase ◽  
Males And Females ◽  
The Mean ◽  
Low Activity

SummaryPost-dexamethasone cortisol and platelet monoamine oxidase (MAO) activity levels were examined in 50 depressed patients. The incidence of non-suppression was significantly greater in patients with high platelet MAO activity than in those with low activity. Similar results were obtained when males and females were analysed separately. The mean 4 p.m. post-dexamethasone cortisol level was significantly higher in those patients who had high MAO activity than in their low MAO counterparts. Moreover, a statistically significant positive correlation was observed between platelet MAO activity and 4 p.m. post-dexamethasone cortisol levels.

Platelet monoamine oxidase activity and life stress as predictors of psychopathology and coping in a community sample

1989 ◽  
Vol 19 (1) ◽  
pp. 79-90 ◽  
Author(s):  
Joanne Boyd Irving ◽  
Robert D. Coursey ◽  
Monte S. Buchsbaum ◽  
Dennis L. Murphy
Keyword(s):  
Monoamine Oxidase ◽  
Mental Health Professionals ◽  
Life Stress ◽  
Stressful Life Events ◽  
Community Sample ◽  
Adult Males ◽  
Platelet Mao ◽  
Mao Activity ◽  
Platelet Mao Activity ◽  
Platelet Monoamine Oxidase

SynopsisThe present study, using a diathesis-stress model, attempted to confirm prior findings with platelet monoamine oxidase (MAO) activity and stress in a middle-aged, non-clinic population. One hundred and seventy-eight adult males from a statewide community club were tested for platelet MAO activity and stressful life events and were also given a variety of psychological measures of both psychopathology and psychosocial coping. The data were examined both for correlations across the total sample and for a comparison of high-risk groups (top and bottom 15% of MAO activity) with a middle MAO group. Low platelet MAO activity was related to a higher incidence of contact with mental health professionals, and more frequent use of alcohol and cigarette smoking. High MAO activity was related to higher levels of anxiety and somatization. High levels of stress were related to increased psychosocial problems reported for female and family members, higher scores on two schizophrenia-related MMPI scales (schizophrenia and paranoia subscales), but fewer idiosyncratic associations, elevated hypomanic, depression, and anxiety scores, increased alcohol use, and increased use of prescribed antianxiety and sedative medication. Neither MAO nor stress were related to current levels of psychosocial coping. Moreover, no interaction effects were uncovered for MAO activity and stress combined.

Platelet Monoamine Oxidase Activity in Acute Schizophrenia: Relationship to Symptomatology and Neuroleptic Medication

1981 ◽  
Vol 139 (1) ◽  
pp. 16-22 ◽  
Author(s):  
Frank Owen ◽  
Rachel C. Bourne ◽  
Timothy J. Crow ◽  
Eve C. Johnstone ◽  
Adnam A. Fadhli
Keyword(s):  
Enzyme Activity ◽  
Negative Symptoms ◽  
Thought Disorder ◽  
Neuroleptic Drugs ◽  
Monoamine Oxidase Activity ◽  
Platelet Mao ◽  
Mao Activity ◽  
Platelet Mao Activity ◽  
Platelet Monoamine Oxidase ◽  
Reduced Activity

SummaryPlatelet MAO activity was assessed in 35 schizophrenics during a trial of the isomers of flupenthixol. Enzyme activity was unrelated to severity of symptoms, the presence of delusions, hallucinations or thought disorder or to negative symptoms. In a few patients MAO activity fluctuated widely with time, but in the group of patients on medication there was a slow decrease in enzyme activity which was significant after 28 days of treatment. Enzyme activity after 14 days' drug treatment was still correlated with activity before treatment, but after 28 days this significant correlation disappeared. Slow effects of neuroleptic drugs on platelet MAO activity may explain previous findings of reduced activity of the enzyme in schizophrenia.

Reduced platelet MAO activity and vulnerability to psychiatric disorders

1980 ◽  
Vol 2 (3) ◽  
pp. 315-321 ◽  
Author(s):  
Ghanshyam N. Pandey ◽  
Elizabeth Dorus ◽  
Rita Shaughnessy ◽  
Moises Gaviria ◽  
Eduardo Val ◽  
...  
Keyword(s):  
Psychiatric Disorders ◽  
Platelet Mao ◽  
Mao Activity ◽  
Platelet Mao Activity

Kinetics and Thermolability of Platelet Monoamine Oxidase in Cluster Headache and Migraine

Cephalalgia ◽  
1984 ◽  
Vol 4 (2) ◽  
pp. 125-134 ◽  
Author(s):  
Elisabet Waldenlind ◽  
Jan Sääf ◽  
Karl Ekbom ◽  
Svante Ross ◽  
Lars-Olof Wahlund ◽  
...  
Keyword(s):  
Monoamine Oxidase ◽  
Cluster Headache ◽  
Control Group ◽  
Enzyme Properties ◽  
Headache Disorders ◽  
Platelet Mao ◽  
Mao Activity ◽  
Platelet Mao Activity ◽  
Platelet Monoamine Oxidase ◽  
C 30

Platelet monoamine oxidase activity (MAO) from 33 cluster headache patients (17 males, 16 females) and 34 migraine patients (16 males, 18 females) was assayed. The kinetic constants (apparent V max and apparent K m ) and the thermolability, measured as the ratio of the platelet MAO activity after and before heat treatment (+52°C, 30 min), were determined. The MAO activity and V max values were significantly lower in cluster headache than in migraine and in both headache disorders compared to a control group (62 males, 66 females). When comparing all groups, K m was not significantly different except for migraine females, who had lower K m values compared to control females. Thermolability was significantly higher in cluster headache than in migraine and in both headache disorders compared to the control group. Smokers of five cigarettes or more per day had significantly lower Vmax values but similar K m and thermolability values compared to those smoking less or nothing. The findings of low maximal velocities and high thermolability of platelet MAO in cluster headache and migraine are suggested to represent constitutionally different enzyme properties.

Genetics of Platelet MAO Activity in Discordant Schizophrenic and Normal Twins

1983 ◽  
Vol 142 (6) ◽  
pp. 560-565 ◽  
Author(s):  
Michael A. Reveley ◽  
Adrianne M. Reveley ◽  
Christine A. Clifford ◽  
Robin M. Murray
Keyword(s):  
Monoamine Oxidase ◽  
Genetic Control ◽  
Platelet Mao ◽  
Mao Activity ◽  
Platelet Mao Activity ◽  
Platelet Monoamine Oxidase ◽  
The Mean ◽  
Mz Twins ◽  
Age And Sex

SummaryPlatelet monoamine oxidase (MAO) activity was compared in four age and sex-matched groups: monozygotic (MZ) twins discordant for schizophrenia, normal MZ twins, normal dizygotic (DZ) twins and unrelated individuals. Among the twin groups, schizophrenic and normal, there was a remarkably consistent degree of genetic control amounting to 70–80 per cent of the variation in activity. The mean platelet MAO activity of the schizophrenic twins was significantly lower than that of controls, but not than that of their psychiatrically well, neuroleptic-free cotwins; indeed the correlation for the MZ twins discordant for schizophrenia was almost exactly the same as that for the normal MZs. Thus, lower platelet MAO activity in schizophrenia, where it is found, is genetically modulated and not the result of the illness or its treatment.

Altered platelet monoamine oxidase activity in affective disorders

1979 ◽  
Vol 9 (4) ◽  
pp. 729-736 ◽  
Author(s):  
John Mann
Keyword(s):  
Affective Disorders ◽  
Lithium Carbonate ◽  
Depressive Illness ◽  
Reactive Depression ◽  
Platelet Mao ◽  
Genetic Mechanisms ◽  
Mao Activity ◽  
Platelet Mao Activity ◽  
Platelet Monoamine Oxidase ◽  
Bipolar Patients

SYNOPSISPlatelet MAO activity was found to be elevated in primary depressive illness, and the severity to correlate positively with MAO activity. The reactive depression subgroup's mean platelet MAO activity was not significantly different from that of the controls. The endogenous group's unipolar and bipolar subgroups had significantly different platelet MAO activity, respectively high and low. The differences in MAO activity between unipolar and bipolar patients appeared to persist in the well state, but not after lithium carbonate therapy. These differences in MAO activity were apparent with the substrate tyramine but not with benzylamine. Altered MAO activity in patients with affective disorders may be determined through genetic mechanisms.

Morbidity risk for psychiatric disorders in families of probands with affective disorders divided according to levels of platelet MAO activity

1985 ◽  
Vol 15 (4) ◽  
pp. 271-279 ◽  
Author(s):  
Lars von Knorring ◽  
Carlo Perris ◽  
Lars Oreland ◽  
Martin Eisemann ◽  
Sonja Holmgren ◽  
...  
Keyword(s):  
Psychiatric Disorders ◽  
Affective Disorders ◽  
Platelet Mao ◽  
Mao Activity ◽  
Platelet Mao Activity ◽  
Morbidity Risk

Low Platelet Monoamine Oxidase Activity in Sensation-Seeking Bullfighters

CNS Spectrums ◽  
1999 ◽  
Vol 4 (12) ◽  
pp. 21-24 ◽  
Author(s):  
José Luis Carrasco ◽  
Jerónimo Sáiz-Ruiz ◽  
Marina Díaz-Marsá ◽  
Jesús César ◽  
Juan José López-Ibor
Keyword(s):  
Monoamine Oxidase ◽  
Sensation Seeking ◽  
Behavioral Pattern ◽  
Control Group ◽  
Platelet Mao ◽  
Isotopic Methods ◽  
Healthy Control ◽  
Mao Activity ◽  
Platelet Mao Activity ◽  
Platelet Monoamine Oxidase

AbstractIn this study, we attempt to demonstrate an association between low platelet monoamine oxidase (MAO) activity, as assessed by isotopic methods, and the stable behavioral pattern of sensation- and risk-seeking of professional bull-fighters. Sixteen professional bullfighters were studied and compared with a control group of 46 healthy control subjects who did not engage in risky jobs or activities. The group of bullfighters had significantly reduced platelet MAO activity compared with the control group (P<0.05). Bullfighters were shown to be significantly more extroverted and sensation-seeking than controls on various temperament scales. A predisposition to engage in risky activities (eg, bullfighting) and sensation-seeking could be partly conditioned by the presence of biological components of personality manifested by a significantly decreased platelet MAO activity.

Platelet Monoamine Oxidase Activity in Schizophrenia

1979 ◽  
Vol 134 (4) ◽  
pp. 366-371 ◽  
Author(s):  
John Mann ◽  
K. M. Thomas
Keyword(s):  
Monoamine Oxidase ◽  
Normal Subjects ◽  
Control Groups ◽  
Platelet Mao ◽  
Duration Of Illness ◽  
Before And After ◽  
Mao Activity ◽  
Platelet Mao Activity ◽  
Platelet Monoamine Oxidase ◽  
Institutionalized Patients

SummaryA study was made of platelet monoamine oxidase (MAO) activity in non-medicated, newly-admitted schizophrenics and institutionalized chronic schizophrenics both on and off medication. These patients were compared to two control groups: normal subjects and brain-damaged institutionalized patients. No relationship was found between platelet MAO activity and the severity or duration of illness, duration of psychotropic medication, presence of auditory hallucinations or institutionalization. Mean platelet MAO activity did not differ significantly between the schizophrenic subgroups and control groups. Thirty-one patients studied before and after treatment with phenothiazines showed no significant change in platelet MAO activity. The findings did not indicate a relationship between schizophrenia, its treatment or outcome and platelet MAO activity.

Sign in / Sign up

Export Citation Format

Share Document