title: Effects of selective serotonin reuptake inhibitors on platelet serotonin parameters in major depressive disorder.
abstract: The effects of treatment with serotonin (5-HT) reuptake inhibitors on platelet 5-HT2 receptors, 5-HT reuptake sites an 5-HT uptake were studied in a double-blind trial comparing two selective serotonin reuptake inhibitors (SSRI), paroxetine, and fluoxetine, for the treatment of major depression. Hamilton Depression Rating Scale (HAM-D) scores and platelet 5-HT parameters were determined in 21 depressed patients at baseline, after 4 and 8 weeks of treatment, and were compared to 21 healthy controls. Antidepressant treatment did not significantly alter the density of 5-HT reuptake sites, labelled with [3H]paroxetine, or 5-HT2 receptors, labelled with [3H]LSD. However, a strong correlation was observed between the HAM-D suicidality item and 5-HT2 receptor density at baseline. A marked increase in platelet 5-HT2 receptors at baseline was observed in suicidal depressed patients compared to those with no suicidal ideation and healthy controls. Changes in [3H]paroxetine Bmax and in [3H]5-HT uptake significantly correlated with change in HAM-D score at 4 and 8 weeks respectively. These results confirm previous reports of an association between suicidality and platelet 5-HT2 receptor upregulation. Our data also lends support to the use of platelet 5-HT parameters as indicators of antidepressant efficacy, particularly in suicidal depressed patients.
authors.affiliation: Department of Psychiatry, University of Ottawa, Ontario, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Bakish
authors.forename: P
authors.initials: P
authors.lastname: Cavazzoni
authors.forename: J
authors.initials: J
authors.lastname: Chudzik
authors.forename: A
authors.initials: A
authors.lastname: Ravindran
authors.forename: P D
authors.initials: PD
authors.lastname: Hrdina
mesh_terms: D000328:Adult; D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism; D003866:Depressive Disorder / Q000097:blood / Q000188:drug therapy*; D004311:Double-Blind Method; D005260:Female; D005473:Fluoxetine / Q000493:pharmacokinetics / Q000627:therapeutic use*; D006801:Humans; D008238:Lysergic Acid Diethylamide / Q000493:pharmacokinetics; D008297:Male; D008875:Middle Aged; D017374:Paroxetine / Q000493:pharmacokinetics / Q000627:therapeutic use*; D010555:Personality Inventory; D011985:Receptors, Serotonin / Q000187:drug effects / Q000502:physiology; D012701:Serotonin / Q000097:blood*; D017367:Selective Serotonin Reuptake Inhibitors / Q000493:pharmacokinetics / Q000627:therapeutic use*
chemical_list: D005473:Fluoxetine; D008238:Lysergic Acid Diethylamide; D017374:Paroxetine; D011985:Receptors, Serotonin; D012701:Serotonin; D017367:Selective Serotonin Reuptake Inhibitors