engleski

Peripheral biochemical variables and antidepressant treatment in major depression

Depression is related to the alterations of the central serotonergic system, and most antidepressants achieve their therapeutic effects by affecting serotonergic transmission, i.e serotonin (5-HT) reuptake, either as inhibitors (i.e. paroxetine, a classical SSRI), or as stimulators (i.e. tianeptine, a novel antidepressant). Since these drugs alter 5-HT uptake in completely opposite ways, and affect also peripheral hormone markers, the aim of the study was a) to evaluate the effects of treatment with paroxetine (20 mg/day) or tianeptine (37.5 mg/day) on platelet and serum 5-HT levels, platelet monoamine oxidase (MAO) activity, plasma cortisol and prolactin levels, in patients with major depression (DSM-IV criteria) ; b) to determine if pretreatment values of these biochemical variables could predict clinical response to treatment. Response was determined according to the 50% fall in HAMD after 4 weeks of treatment. Paroxetine treatment decreased significantly (F=11.39 ; df=4, 50 ; p<0.001) platelet 5-HT levels in responders and nonresponders. Before paroxetine treatment nonresponders had higher platelet 5-HT levels than responders, or than healthy control. Platelet 5-HT levels were similar (F=1.51 ; df=4, 62 ; p=0.21) among patients treated with tianeptine and in healthy controls. Serum 5-HT levels differed in tianeptine (F=3.28 ; df=4, 52 ; p=0.018), but not in paroxetine (F=1.60 ; df=4, 50 ; p=0.19) treated patients, when compared to healthy controls, but both treatments failed to affect serum 5-HT values in responders or nonresponders. Platelet MAO activity did not differ between healthy controls and responders or nonresponders to paroxetine (F=0.36 ; df=4, 50 ; p=0.83), or tianeptine (F=0.63 ; df=4, 62 ; p=0.64). Plasma PRL levels were significantly higher in responders after paroxetine treatment when compared to responders at baseline (F=3.30 ; df=4, 50 ; p<0.018), but did not differ significantly from the values in healthy controls. No significant difference in plasma PRL levels was detected between patients treated with tianeptine (F=1.41, df=4, 62, p=0.24) and healthy controls. Treatment with paroxetine did not alter (F=1.01 ; df=4, 50 ; p=0.41) plasma cortisol levels in responders and nonresponders or in healthy controls. Plasma cortisol levels differed slightly (F=2.72 ; df=4, 62 ; p=0.037) in responders and nonresponders to tianeptine and in healthy controls, but without any effect of the treatment per se on patients. Our results show a) different and/or opposite effects of two antidepressants on peripheral 5-HT and hormone variables ; and b) pretreatment platelet 5-HT levels, but not serum 5-HT values, platelet MAO activity or plasma cortisol or prolactin levels, might predict therapeutic outcome to paroxetine, but not to tianeptine treatment.

peripheral biochemical variables; antidepressants

nije evidentirano