Serotonin and 5-hydroxyindoleacetic acid in plasma. Potential use as peripheral measures of MAO-A activity
We have explored the possibility of using measures of 5-HT (extracellular 5-HT and 5-HIAA in blood) as peripheral indexes of MAO activity. Depressed patients treated with phenelzine for 6 weeks display a dramatic increase of plasma 5-HT (270% of basal values) together with a decrease of plasma 5-HIAA. After treatment with irreversible MAO inhibitors, rat plasma 5-HIAA decreased in a similar fashion than MAO-A activity in liver, lungs and brain, measured using 5-HT as substrate. These results support the use of plasma 5-HT and 5-HIAA in humans to evaluate the action of MAOI on the serotonergic system.
KeywordsMonoamine Oxidase Inhibitor Peripheral Measure Plasma Serotonin Platelet Monoamine Oxidase Peripheral Index
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- Artigas F, Sarrias MJ, Martínez E, Gelpí E (1985) Serotonin in body fluids. Characterization of human plasmatic and cerebrospinal fluid pools by means of a new HPLC method. Life Sci 37:441–447.Google Scholar
- Gillis CN (1985) Peripheral metabolism of serotonin. In: Vanhoutte PM (ed) Serotonin and the cardiovascular system. Raven Press, New York, pp 27–36.Google Scholar
- Heninger GR, Charney DS (1987) Mechanism of action of antidepressant treatments: implications for the etiology and treatment of depressive disorders. In: Meltzer HY (ed) Psychopharmacology: the third generation of progress. Raven Press, New York, pp 535–544.Google Scholar
- Young WF, Laws ER, Sharbrough FW, Weinshilboum RM (1986) Human monoamine oxidase. Lack of brain and platelet correlation. Arch Gen Psychiatry 43:604–609.Google Scholar