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Thermostabilization, Expression, Purification, and Crystallization of the Human Serotonin Transporter Bound to S-citalopram
Published on: November 27, 2016
Serotonin transporter occupancy with TCAs and SSRIs: a PET study in patients with major depressive disorder
Johan Lundberg1, Mikael Tiger, Mikael Landén
1Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden. johan.lundberg@ki.se
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.
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