Decreased defluorination using the novel betacell imaging agent [18F]FE-DTBZ-d4 in pigs examined by PET

31Citations
Citations of this article
18Readers
Mendeley users who have this article in their library.

This artice is free to access.

Abstract

Background: Fluorine-18 dihydrotetrabenazine [DTBZ] analogues, which selectively target the vesicular monoamine transporter 2 [VMAT2], have been extensively studied for in vivo quantification of beta cell mass by positron-emission tomography [PET]. This study describes a novel deuterated radioligand [18F]fluoroethyl [FE]-DTBZd4, aimed to increase the stability against in vivo defluorination previously observed for [18F]FE-DTBZ. Methods: [18F]FE-DTBZ-d4 was synthesized by alkylation of 9-O-desmethyl-(+)-DTBZ precursor with deuterated [18F] FE bromide ([18F]FCD2CD2Br). Radioligand binding potential [BP] was assessed by an in vitro saturation homogenate binding assay using human endocrine and exocrine pancreatic tissues. In vivo pharmacokinetics and pharmacodynamics [PK/PD] was studied in a porcine model by PET/computed tomography, and the rate of defluorination was quantified by compartmental modeling. Results: [18F]FE-DTBZ-d4 was produced in reproducible good radiochemical yield in 100 ± 20 min. Radiochemical purity of the formulated product was > 98% for up to 5 h with specific radioactivities that ranged from 192 to 529 GBq/μmol at the end of the synthesis. The in vitro BP for VMAT2 in the islet tissue was 27.0 ± 8.8, and for the exocrine tissue, 1.7 ± 1.0. The rate of in vivo defluorination was decreased significantly (kdefluorination = 0.0016 ± 0.0007 min-1) compared to the non-deuterated analogue (kdefluorination = 0.012 ± 0.002 min-1), resulting in a six fold increase in half-life stability. Conclusions: [18F]FE-DTBZ-d4 has similar PK and PD properties for VMAT2 imaging as its non-deuterated analogue [18F]FE-DTBZ in addition to gaining significantly increased stability against defluorination. [18F]FE-DTBZ-d4 is a prime candidate for future preclinical and clinical studies on focal clusters of beta cells, such as in intramuscular islet grafts. © 2011 Jahan et al.

Cite

CITATION STYLE

APA

Jahan, M., Eriksson, O., Johnström, P., Korsgren, O., Sundin, A., Johansson, L., & Halldin, C. (2011). Decreased defluorination using the novel betacell imaging agent [18F]FE-DTBZ-d4 in pigs examined by PET. EJNMMI Research, 1(1), 1–13. https://doi.org/10.1186/2191-219X-1-33

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free