The Tryptophan System in Cocaine-Induced Depression.

摘要: Major depression disorder (MDD) is the most prevalent psychiatric comorbid condition in cocaine use (CUD). The MDD might be primary-MDD (CUD-primary-MDD) or cocaine-induced (CUD-induced-MDD), and their accurate diagnoses treatment a challenge for improving prognoses. This study aimed to assess tryptophan/serotonin (Trp/5-HT) system with acute tryptophan depletion test (ATD), kynurenine pathway subjects CUD-primary-MDD, CUD-induced-MDD, healthy controls. ATD was performed randomized, double-blind, crossover, placebo-controlled design. Markers of enzymatic activity indoleamine 2,3-dioxygenase/tryptophan 2,3-dioxygenase, aminotransferase (KAT) kynureninase were also established. Following ATD, we observed decrease Trp levels all groups. Comparison between CUD-induced-MDD revealed significant differences 5-HT plasma concentrations (512 + 332 ng/mL vs. 107 127 ng/mL, p = 0.039) Kyn/5-HT ratio (11 15 112 136; 0.012), whereas there no CUD-primary-MDD MDD. Effect size coefficients show gradient targeted markers (d range 0.72-1.67). Results suggest different pathogenesis lower participation system, probably more related other neurotransmitter pathways accordingly suggesting need pharmacological approach.