[76Br]bromolisuride: a new tool for quantitative in vivo imaging of D-2 dopamine receptors

Bromolisuride, an ergoline derivative, was labeled with the positron emitter radionuclide, bromine 76. In vitro and in vivo binding and competition studies in rats demonstrated a high affinity (KD = 0.3 nM) and a high specificity of this new radioligand for D-2 dopamine receptors. PET kinetic studies in baboons showed an accumulation of [76Br]bromolisuride in the striatum which reached a maximum 30 min post-injection and which could be displaced by haloperidol. All these results indicated that this new ligand is certainly suitable for the non-invasive in vivo quantitative imaging of D-2 dopamine receptor sites in human brain.