Decreased plasma serotonin in melancholic patients: a study with clomipramine.
Eighteen unmedicated patients suffering from major depressive disorder with melancholia (DSM-III) were examined for abnormalities in peripheral serotonin (5-HT) and related metabolites. Serotonin in platelet-free plasma and in platelets from melancholics was significantly reduced to 30% and 60% of their respective control values. Plasma 5-hydroxyindoleacetic acid was also found to be reduced, but not significantly. Other plasma compounds related to 5-HT (indoleacetic acid, total tryptophan, and free tryptophan) were found to be unchanged in these patients. Of all variables, only platelet 5-HT was affected while patients were on clomipramine (CIM) treatment. After 2 weeks on CIM (100-150 mg/day, orally), platelet 5-HT was reduced to 8% of pretreatment values, but plasma 5-HT did not change and continued to be reduced upon clinical recovery. The existence of a distinct pool of plasma 5-HT that is clearly independent of the platelet pool is indicated by the differences observed in plasma and platelet 5-HT during CIM treatment, as well as by previous data from this laboratory. The very marked decrease in plasma 5-HT levels may be in accord with the central nervous system changes reported in depression and suggests the possibility of using plasma 5-HT as a peripheral indicator of abnormal serotonin function in melancholia.
Sarrias
M J
MJ
Department of Neurochemistry, CSIC, Barcelona, Spain.
Artigas
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Martínez
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Gelpí
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Alvarez
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Udina
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Casas
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D000368:Aged; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism; D002997:Clomipramine / Q000627:therapeutic use*; D003866:Depressive Disorder / Q000097:blood / Q000188:drug therapy* / Q000523:psychology; D005260:Female; D006801:Humans; D008950:MMPI; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D012701:Serotonin / Q000097:blood*
D012701:Serotonin; D002997:Clomipramine