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06:32
Dynamic Multiparameter Platelet Function Assessment Using a Capacitive Biosensor
Published on: May 2, 2025
Differences in platelet enzyme activity between alcoholics and nonalcoholics
B Tabakoff1, P L Hoffman, J M Lee
1National Institute on Alcohol Abuse and Alcoholism, Bethesda, Md 20892.
The New England Journal of Medicine
|January 21, 1988
Summary
Long-term heavy alcohol consumption alters enzymes in blood platelets, affecting monoamine oxidase inhibition and adenylate cyclase activity. These changes may indicate excessive alcohol use or a predisposition to alcoholism.
Area of Science:
- Biochemistry
- Neuroscience
- Addiction Research
Background:
- Blood platelets serve as accessible biomarkers reflecting brain enzyme activity.
- Long-term excessive ethanol consumption may impact enzymatic functions within the brain.
Purpose of the Study:
- To investigate the effects of chronic heavy ethanol intake on platelet enzyme activity.
- To assess monoamine oxidase and adenylate cyclase activity in alcoholics versus controls.
Main Methods:
- Assayed monoamine oxidase (MAO) and adenylate cyclase (AC) activity in platelet membranes.
- Compared enzyme inhibition by ethanol (in vitro) and AC stimulation in alcoholics and controls.
- Utilized discriminant analysis to classify subjects based on enzyme activity.
Main Results:
- Platelet MAO inhibition by ethanol was significantly higher in alcoholics.
- Cesium fluoride-stimulated AC activity was significantly lower in alcoholics, even after prolonged abstinence.
- Enzyme activity measures correctly classified a high percentage of alcoholics and controls.
Conclusions:
- Altered platelet enzyme activity, specifically MAO inhibition and AC stimulation, is linked to alcoholism.
- These enzymatic changes are long-lasting and may serve as indicators of excessive alcohol consumption or predisposition.
- Platelet enzyme assays show potential for diagnosing alcohol use disorders and identifying at-risk individuals.
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