Firk Christine, Markus C Rob
Department of Clinical Psychological Science, Faculty of Psychology and Neuroscience, Maastricht University, P.O. Box 616, 6200, MD, Maastricht, The Netherlands.
Psychopharmacology (Berl). 2009 May;203(4):805-18. doi: 10.1007/s00213-008-1428-9. Epub 2008 Dec 16.
Polymorphisms of the serotonin transporter gene (5-HTTLPR) may be associated with increased vulnerability to acute tryptophan depletion (ATD) and depression vulnerability especially following stressful life events.
The aim of the present study was to investigate the effects of ATD in subjects with different 5-HTTLPR profiles before and after stress exposure on affective and cognitive-attentional changes.
Eighteen subjects with homozygotic short alleles (S'/S') and 17 subjects with homozygotic long alleles (L'/L') of the 5-HTTLPR participated in a double-blind, placebo-controlled, crossover design to measure the effects of ATD on mood, memory, and attention before and after acute stress exposure.
ATD lowered mood in all subjects independent of genotype. In S'/S' genotypes, mild acute stress increased depressive mood and in L'/L' genotypes increased feelings of vigor. Furthermore, S'/S' genotypes differed from L'/L' genotypes on measures of attention independent of treatment and memory following ATD.
Polymorphisms of the 5-HTTLPR differentially affect responses to mild stress and ATD, suggesting greater vulnerability of S'/S' carriers to serotonergic manipulations and supporting increased depression vulnerability.
血清素转运体基因（5-HTTLPR）的多态性可能与急性色氨酸耗竭（ATD）易感性增加以及抑郁易感性有关，尤其是在经历应激性生活事件之后。
本研究旨在调查在应激暴露前后，不同5-HTTLPR基因型的受试者中ATD对情感和认知注意力变化的影响。
18名携带5-HTTLPR纯合短等位基因（S'/S'）的受试者和17名携带纯合长等位基因（L'/L'）的受试者参与了一项双盲、安慰剂对照、交叉设计的实验，以测量急性应激暴露前后ATD对情绪、记忆和注意力的影响。
ATD会降低所有受试者的情绪，与基因型无关。在S'/S'基因型中，轻度急性应激会加重抑郁情绪，而在L'/L'基因型中则会增强活力感。此外，在ATD后的注意力测量方面，S'/S'基因型与L'/L'基因型存在差异，且与治疗和记忆无关。
5-HTTLPR的多态性对轻度应激和ATD的反应有不同影响，表明S'/S'携带者对血清素操纵更为敏感，支持了其抑郁易感性增加的观点。
