We found that treatment of both differentiated dopaminergic-like SH-SY5Y cells and rat midbrain slices with the dopamine D2 receptor (D2R) agonist, << quinpirole >>, triggered an increase in the expression of GDNF that was temporally preceded by an increase in the levels of [[ zinc-finger protein 268 ]] (Zif268), a DNA-binding transcription factor encoded by an immediate-early gene.