The effect of citalopram treatment on platelet serotonin function in panic disorders.
We investigated the effect of the selective serotonin reuptake inhibitor (SSRI) citalopram after 6-8 weeks and 6 months of treatment on clinical and peripheral indexes for central serotonergic function: platelet [14C]serotonin uptake and [3H]paroxetine- and [3H]LSD-binding to platelets membranes in 33 patients with panic disorder. Basal data from patients were compared with data from a control material consisting of 33 healthy volunteers. Bmax for platelet [3H]paroxetine binding was significantly lower in patients than in controls. There were no differences in serotonin uptake or [3H]LSD-binding between patients and controls. The degree of anxiety and depression was assessed using the Beck Anxiety Inventory (BAI) and Beck Depression Inventory self-assessment scales, and the Clinical Anxiety Scale and the Montgomery Asberg Depression Rating Scale for clinical evaluation. Complete remission was found in one third of the patients after 6-8 weeks and in two-thirds after 6 months of treatment. The reduction in assessment scores was parallelled with similar reductions in platelet 5-HT2-receptor density, [3H]LSD affinity variable (Kd) and Vmax for platelet [14C]5-HT uptake. Citalopram treatment did not alter Bmax and Kd for platelet [3H]paroxetine-binding. A positive correlation was found between Vmax for the platelet [14C]5-HT uptake and BAI after 6 months citalopram treatment. The present study shows that citalopram has a therapeutic effect in panic disorders. A prerequisite of responding to treatment might be plasticity in the serotonergic system.
Neuger
J
J
Karolinska Institute, Institution of Clinical Neuroscience, Department of Psychiatry, St Göran's Hospital, Stockholm, Sweden. Jolanta.Neuger@cspo.sll.se
Wistedt
B
B
Sinner
B
B
Aberg-Wistedt
A
A
Stain-Malmgren
R
R
D000328:Adult; D001007:Anxiety; D001792:Blood Platelets; D015283:Citalopram / Q000494:pharmacology* / Q000627:therapeutic use; D003863:Depression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016584:Panic Disorder / Q000188:drug therapy*; D011985:Receptors, Serotonin / Q000187:drug effects* / Q000502:physiology; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use
D015283:Citalopram; D011985:Receptors, Serotonin; D017367:Selective Serotonin Reuptake Inhibitors