PD 128907

PD 128907 is a D3 receptor ligand with activities of activating dopamine receptors, inhibiting cell firing, and inhibiting dopamine release. The active (+) enantiomer of PD 128907 has high affinity and selectivity for rat D3 dopamine receptors. PD 128907 inhibits cell firing in the ventral tegmental area and substantia nigra pars compacta with EC50 values of 33nM and 38nM, respectively. PD 128907 also inhibits dopamine release in the caudate putamen with an EC50 of 66nM. However, the selective D2 receptor antagonist L-741,626 has high affinity for receptors activated by PD 128907, indicating that the effects of PD 128907 are more likely on D2 autoreceptors rather than D3 dopamine receptor subtypes.