Journal of Neural Transmission

, Volume 114, Issue 5, pp 635–639

Midbrain serotonin transporter binding potential measured with [11C]DASB is affected by serotonin transporter genotype

  • M. Reimold
  • M. N. Smolka
  • G. Schumann
  • A. Zimmer
  • J. Wrase
  • K. Mann
  • X.-Z. Hu
  • D. Goldman
  • G. Reischl
  • C. Solbach
  • H.-J. Machulla
  • R. Bares
  • A. Heinz
Article

DOI: 10.1007/s00702-006-0609-0

Cite this article as:
Reimold, M., Smolka, M., Schumann, G. et al. J Neural Transm (2007) 114: 635. doi:10.1007/s00702-006-0609-0

Summary

Background. Homozygote carriers of two long (L) alleles of the serotonin transporter (5-HTT) regulatory region displayed in vitro a twofold increase in 5-HTT expression compared with carriers of one or two short (S) alleles. However, in vivo imaging studies yielded contradictory results. Recently, an A > G exchange leading to differential transcriptional activation of 5-HTT mRNA in lymphobalstoid cell lines was discovered in the 5-HTT regulatory region. In vitro and in vivo evidence suggests that [11C]DASB, a new 5-HTT ligand offers some advantages over the ligands used in previous studies in measuring 5-HTT density independent of synaptic levels of serotonin.

Method. We assessed 5-HTT binding potential (BP2) in the midbrain of 19 healthy subjects with positron emission tomography and [11C]DASB. Accounting for the hypothesized functional similarity of LG and S in driving 5-HTT transcription, we assessed whether LALA homozygotes display increased midbrain BP2 compared with carriers of at least one S allele.

Results. BP2 in the midbrain was significantly increased in LALA homozygotes compared with carriers of at least one S allele. Interestingly, the genotype effect on the midbrain was significantly different from that on the thalamus and the amygdala where no group differences were detected.

Conclusions. This in vivo study provides further evidence that subjects homozygous for the LA allele display increased expression of 5-HTT in the midbrain, the origin of central serotonergic projections.

Keywords: 5-HTT, SCL6A4, PET, DASB

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • M. Reimold
    • 1
  • M. N. Smolka
    • 3
  • G. Schumann
    • 3
    • 4
  • A. Zimmer
    • 3
  • J. Wrase
    • 5
  • K. Mann
    • 3
  • X.-Z. Hu
    • 6
  • D. Goldman
    • 6
  • G. Reischl
    • 2
  • C. Solbach
    • 2
  • H.-J. Machulla
    • 2
  • R. Bares
    • 1
  • A. Heinz
    • 3
    • 5
  1. 1.Department of Nuclear Medicine and PET CenterUniversity of TübingenTübingenGermany
  2. 2.RadiopharmacyUniversity of TübingenTübingenGermany
  3. 3.Department of Addictive Behavior and Addiction MedicineCentral Institute of Mental HealthMannheimGermany
  4. 4.Section of Addiction Biology, Institute of PsychiatryKing’s CollegeLondonU.K.
  5. 5.Department of PsychiatryCharité University Medicine Berlin (CCM)BerlinGermany
  6. 6.National Institute of Alcohol Abuse and AlcoholismNIHBethesdaU.S.A.