PET EXAMINATION OF THE MONOAMINE TRANSPORTER WITH [C-11] BETA-CIT AND [C-11] BETA-CFT IN EARLY PARKINSONS-DISEASE

The monoamine transporter was studied in 4 healthy controls and 5 patients with early Parkinson's disease (PD), who had not received any antiparkinsonian medication, by means of positron emission tomography (PET) using two novel ligands, [C-11]beta-CIT and [C-11]P-CFT. Both ligands showed highest uptake in the striatum. There was intermediate accumulation of activity in the thalamus and midbrain, which was more marked for [C-11]beta-CIT than for [C-11]beta-CFT. In the cortical areas, uptake of both ligands was not different from that seen in the cerebellum. In the controls, the putamen-to-cerebellum and caudate-to-cerebellum ratios for [C-11]beta-CFT were higher than those for [C-11]beta-CIT (putamen: 3.15 +/- 0.39 for [C-11]beta-CFT, and 1.84 +/- 0.10 for [C-11]beta-CIT; caudate: 3.15 +/- 0.31 for [C-11]beta-CFT, and 1.95 +/- 0.17 for [C-11]beta-CIT). Reduction from mean control value in PD patients was greater for [C-11]beta-CFT (45% in the putamen contralateral to the predominant symptoms, P < 0.001) than for [C-11]beta-CIT (20%, P > 0.05). [C-11]beta-CFT uptake in the caudate nucleus was also diminished in PD patients (to 80% of the control mean, P < 0.05), whereas [C-11]beta-CIT was within normal range (reduced to 90% of the control mean). These results indicate that both [C-11]beta-CIT and [C-11]beta-CFT are useful PET ligands to study brain monoamine transporter in healthy controls and in patients with PD. However, [C-11]beta-CFT seems superior to [C-11]beta-CIT in this respect. (C) 1995 Wiley-Liss, Inc.