Demonstration of pulmonary beta2-adrenergic receptor binding in vivo with [18F]fluoroethyl-fenoterol in a guinea pig model.

A Helisch, E Schirrmacher, O Thews, R Schirrmacher, H G Buchholz, W Dillenburg, S Höhnemann, J Tillmanns, I Wessler, R Buhl, F Rösch, P Bartenstein

Department of Nuclear Medicine, University Hospital, Langenbeckstrasse 1, 55101 Mainz, Germany. helisch@nuklear.klinik.uni-mainz.de

European journal of nuclear medicine and molecular imaging 2005 Nov

filter terms:

The new beta2 radioligand (R,R)(S,S) 5-(2-(2-[4-(2-[18F]fluoroethoxy)phenyl]-1-methylethylamino)-1-hydroxyethyl)-benzene-1,3-diol ([18F]FE-fenoterol; [18F]FEFE), a fluoroethylated derivative of racemic fenoterol, was evaluated in vivo and ex vivo using a guinea pig model. Dynamic PET studies over 60 min with [(18)F]FEFE were performed in nine Hartley guinea pigs in which a baseline (group 1, n=3), a predose (group 2, n=3; 2 mg/kg fenoterol 5 min prior to injection of [18F]FEFE) or a displacement study (group 3, n=3; 2 mg/kg fenoterol 5 min post injection of [18F]FEFE) was conducted. In all animal groups, the lungs could be visualised and semi-quantified separately by calculating uptake ratios to non-specific binding in the neck area. Premedication with non-radioactive fenoterol and displacement tests showed significant reduction of lung uptake, by 94% and 76%, respectively. These data demonstrate specific binding of the new radioligand to the pulmonary beta2-receptors in accordance with ex vivo measurements. Therefore, [18F]FEFE seems to be suitable for the in vivo visualisation and quantification of the pulmonary beta2-receptor binding in this animal model.

Citation

A Helisch, E Schirrmacher, O Thews, R Schirrmacher, H G Buchholz, W Dillenburg, S Höhnemann, J Tillmanns, I Wessler, R Buhl, F Rösch, P Bartenstein. Demonstration of pulmonary beta2-adrenergic receptor binding in vivo with [18F]fluoroethyl-fenoterol in a guinea pig model. European journal of nuclear medicine and molecular imaging. 2005 Nov;32(11):1324-8