title: Serotonin transporter occupancy with TCAs and SSRIs: a PET study in patients with major depressive disorder.
abstract: The aim of the present clinical positron emission tomography study was to examine if the 5-HTT is a common target, both for tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SSRIs). Serotonin transporter (5-HTT) occupancy was estimated during treatment with TCA, SSRI and mirtazapine in 20 patients in remission from depression. The patients were recruited from out-patient units and deemed as responders to antidepressive treatment. The radioligand [¹¹C]MADAM was used to determine the 5-HTT binding potential. The mean 5-HTT occupancy was 67% (range 28-86%). There was no significant difference in 5-HTT occupancy between TCA (n=5) and SSRI (n=14). 5-HTT affinity correlated with the recommended clinical dose. Mirtazapine did not occupy the serotonin transporter. The results support that TCAs and SSRIs have a shared mechanism of action by inhibition of 5-HTT.
authors.affiliation: Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden. johan.lundberg@ki.se
authors.forename: Johan
authors.initials: J
authors.lastname: Lundberg
authors.forename: Mikael
authors.initials: M
authors.lastname: Tiger
authors.forename: Mikael
authors.initials: M
authors.lastname: Landén
authors.forename: Christer
authors.initials: C
authors.lastname: Halldin
authors.forename: Lars
authors.initials: L
authors.lastname: Farde
mesh_terms: D000328:Adult; D000929:Antidepressive Agents, Tricyclic / Q000494:pharmacology* / Q000627:therapeutic use; D001596:Benzylamines / Q000493:pharmacokinetics; D002250:Carbon Radioisotopes / Q000493:pharmacokinetics; D003865:Major Depressive Disorder / Q000000981:diagnostic imaging* / Q000188:drug therapy; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011485:Protein Binding / Q000187:drug effects; D050486:Serotonin Plasma Membrane Transport Proteins / Q000378:metabolism*; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D055815:Young Adult
chemical_list: D000929:Antidepressive Agents, Tricyclic; D001596:Benzylamines; D002250:Carbon Radioisotopes; D050486:Serotonin Plasma Membrane Transport Proteins; D017367:Selective Serotonin Reuptake Inhibitors; C470437:N,N-dimethyl-2-(2-amino-4-methylphenylthio)benzylamine