Article

Early-life blockade of the 5-HT transporter alters emotional behavior in adult mice.

Sackler Institute for Developmental Psychobiology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.
Science (Impact Factor: 31.48). 10/2004; 306(5697):879-81. DOI: 10.1126/science.1101678
Source: PubMed

ABSTRACT Reduced serotonin transporter (5-HTT) expression is associated with abnormal affective and anxiety-like symptoms in humans and rodents, but the mechanism of this effect is unknown. Transient inhibition of 5-HTT during early development with fluoxetine, a commonly used serotonin selective reuptake inhibitor, produced abnormal emotional behaviors in adult mice. This effect mimicked the behavioral phenotype of mice genetically deficient in 5-HTT expression. These findings indicate a critical role of serotonin in the maturation of brain systems that modulate emotional function in the adult and suggest a developmental mechanism to explain how low-expressing 5-HTT promoter alleles increase vulnerability to psychiatric disorders.

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