Send to:

Choose Destination
See comment in PubMed Commons below
J Psychiatry Neurosci. 2006 Sep;31(5):333-9.

Fluoxetine-induced alterations in human platelet serotonin transporter expression: serotonin transporter polymorphism effects.

Author information

  • 1Department of Psychiatry, University of Michigan and Ann Arbor VAMC, Ann Arbor, MI 48105, USA.



Long-term antidepressant drug exposure may regulate its target molecule - the serotonin transporter (SERT). This effect could be related to an individual's genotype for an SERT promoter polymorphism (human serotonin transporter coding [5-HTTLPR]). We aimed to determine the effects of fluoxetine exposure on human platelet SERT levels.


We harvested platelet samples from 21 healthy control subjects. The platelets were maintained alive ex vivo for 24 hours while being treated with 0.1 muM fluoxetine or vehicle. The effects on SERT immunoreactivity (IR) were then compared. Each individual's SERT promoter genotype was also determined to evaluate whether fluoxetine effects on SERT were related to genotype.


Fluoxetine exposure replicably altered SERT IR within individuals. Both the magnitude and the direction of effect were related to a person's SERT genotype. People who were homozygous for the short gene (SS) displayed decreased SERT IR, whereas those who were homozygous for the long gene (LL) demonstrated increased SERT IR. A mechanistic experiment suggested that some individuals with the LL genotype might experience increased conversion of complexed SERT to primary SERT during treatment.


These preliminary results suggest that antidepressant effects after longer-term use may include changes in SERT expression levels and that the type and degree of effect may be related to the 5-HTTLPR polymorphism.

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for The Canadian Medical Association Icon for PubMed Central
    Loading ...
    Write to the Help Desk