Title
Varenicline increases in vivo striatal dopamine <tex>$D_{2/3}$</tex> receptor binding : an ultra-high-resolution pinhole <tex>$[^{123}I]IBZM$</tex> SPECT study in rats Varenicline increases in vivo striatal dopamine <tex>$D_{2/3}$</tex> receptor binding : an ultra-high-resolution pinhole <tex>$[^{123}I]IBZM$</tex> SPECT study in rats
Author
Faculty/Department
Faculty of Pharmaceutical, Biomedical and Veterinary Sciences. Pharmacy
Faculty of Medicine and Health Sciences
Publication type
article
Publication
Subject
Human medicine
Source (journal)
Nuclear medicine and biology
Volume/pages
39(2012) :5 , p. 640-644
ISSN
0969-8086
Carrier
E
Target language
English (eng)
Full text (Publishers DOI)
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&#8270;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.
E-info
https://repository.uantwerpen.be/docman/iruaauth/9d7503/9c8f352292f.pdf