Format

Send to

Choose Destination
Nucl Med Biol. 2012 Jul;39(5):640-4. doi: 10.1016/j.nucmedbio.2011.11.006. Epub 2012 Jan 20.

Varenicline increases in vivo striatal dopamine D2/3 receptor binding: an ultra-high-resolution pinhole [123I]IBZM SPECT study in rats.

Author information

1
Department of Psychiatry and Amsterdam Institute for Addiction Research, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands. c.l.crunelle@amc.uva.nl

Abstract

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‚Āétreatment 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.

PMID:
22261145
DOI:
10.1016/j.nucmedbio.2011.11.006
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center