In vivo imaging of adenovirus-mediated over-expression of dopamine D-2 receptors in rat striatum by positron emission tomography

PET was used to provide in vivo imaging of the over-expression of dopamine D-2 receptor (D2R) induced by adenovirus vector-mediated gene transfer in r at striatum. The uptake of three kinds of D2R-specific ligands, [C-11]raclo pride, [C-11]nemonapride and [C-11]N-methylspiperone, measured by PET was h igher in the striatum injected with the vectors for D2R than the contralate ral striatum injected with a control vector 2-3 days after injection. Howev er, the uptake of [C-11]SCH 23390, a dopamine D-1 receptor specific ligand, or [C-11]beta-CIT-FP, a dopamine transporter specific tracer, was not diff erent between bilateral striata. Co-injection of excess unlabeled racloprid e inhibited the uptake of [C-11]raclopride. At day 16 the increased uptake of [C-11]raclopride declined to basal level, consistent with past in vitro assessment of this vector. In vivo imaging of D2R will permit longitudinal assessment of the efficiency of this and similar vectors in rat brain that can be related to functional changes being observed. NeuroReport 11:743-748 (C) 2000 Lippincott Williams & Wilkins.