Interactive effects of sex and 5-HTTLPR on mood and impulsivity during tryptophan depletion in healthy people.
BACKGROUND
Serotonin (5-HT) plays a central role in mood regulation and impulsivity. We studied whether healthy men and women react differently on mood and impulsivity measures during acute tryptophan depletion (ATD). We also studied the relative contribution of a functional length triallelic polymorphism in the promoter region of the serotonin transporter, designated 5-HTTLPR, to the behavioral responses to ATD.


METHODS
Thirty-nine men and 44 women participated in a randomized, double-blind, parallel group ATD study. Behavioral measures of impulsivity and mood were obtained.


RESULTS
During ATD, women reported mood reduction and showed a cautious response style, which is commonly associated with depression. Men showed an impulsive response style and did not report mood reduction. The 5-HTTLPR influenced the mood response to ATD in women.


CONCLUSIONS
Healthy men became more impulsive, whereas healthy women showed mood reduction in response to ATD. This suggests that 5-HT could be one mechanism contributing to the sex differences in the prevalence of mood and impulsivity disorders. The influence of 5-HTTLPR on mood responses in women further substantiates the relevance of this variant in the pathophysiology of at least a subgroup of patients with major depressive disorder.
Walderhaug
Espen
E
Department of Psychology, University of Oslo, Blindern, 0317 Oslo, Norway. espen.walderhaug@psykologi.uio.no
Magnusson
Andres
A
Neumeister
Alexander
A
Lappalainen
Jaakko
J
Lunde
Hilde
H
Refsum
Helge
H
Landrø
Nils Inge
NI
D000328:Adult; D000339:Affect / Q000502:physiology*; D003865:Major Depressive Disorder / Q000453:epidemiology / Q000235:genetics / Q000503:physiopathology; D004311:Double-Blind Method; D005260:Female; D005838:Genotype; D006801:Humans; D007175:Impulsive Behavior / Q000235:genetics / Q000503:physiopathology*; D008297:Male; D019964:Mood Disorders / Q000453:epidemiology; D009664:Norway / Q000453:epidemiology; D011110:Polymorphism, Genetic / Q000235:genetics / Q000502:physiology; D015995:Prevalence; D011401:Promoter Regions, Genetic / Q000235:genetics / Q000502:physiology; D012701:Serotonin / Q000235:genetics / Q000502:physiology*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics / Q000502:physiology*; D014364:Tryptophan / Q000097:blood / Q000172:deficiency* / Q000378:metabolism
C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D012701:Serotonin; D014364:Tryptophan