• Cleo Crunelle
  • TC DE WIT
  • K de Bruin
  • Ruud M Ramakers
  • F van der Have
  • FJ BEEKMAN
  • W. Van Den Brink
  • J Booij
INTRODUCTION:

Ex vivo storage phosphor imaging rat studies reported increased brain dopamine D2/3 receptor (DRD2/3) availability following treatment with varenicline, a nicotinergic drug. However, ex vivo studies can only be performed using cross-sectional designs. Small-animal imaging offers the opportunity to perform serial assessments. We evaluated whether high-resolution pinhole single photon emission computed tomography (SPECT) imaging in rats was able to reproduce previous ex vivo findings.

METHODS:

Rats were imaged for baseline striatal DRD2/3 availability using ultra-high-resolution pinhole SPECT (U-SPECT-II) and [123I]IBZM as a radiotracer, and randomized to varenicline (n=7; 2 mg/kg) or saline (n=7). Following 2 weeks of treatment, a second scan was acquired.

RESULTS:

Significantly increased striatal DRD2/3 availability was found following varenicline treatment compared to saline (time⁎treatment effect): posttreatment difference in binding potential between groups corrected for initial baseline differences was 2.039 (P=.022), indicating a large effect size (d=1.48).

CONCLUSIONS:

Ultra-high-resolution pinhole SPECT can be used to assess varenicline-induced changes in DRD2/3 availability in small laboratory animals over time. Future small-animal studies should include imaging techniques to enable repeated within-subjects measurements and reduce the amount of animals.
Original languageEnglish
Pages (from-to)640-644
Number of pages5
JournalNuclear Medicine & Biology
Volume39
Issue number5
DOIs
Publication statusPublished - 2011

ID: 49996315