PD 168568 is a dopamine D4 receptor antagonist (Ki = 8.8 nM).1 It is selective for dopamine D4 over D2 receptors (Ki = 1,842 nM). PD 168568 (3 mg/kg) reverses amphetamine-induced hyperlocomotion in rats. It also inhibits the growth of glioblastoma neural stem cells when used at concentrations of 25 and 50 µM.2
1.Belliotti, T.R., Brink, W.A., Kesten, S.R., et al.Isoindolinone enantiomers having affinity for the dopamine D4 receptorBioorg. Med. Chem. Lett.8(12)1499-1502(1998) 2.Dolma, S., Selvadurai, H.J., Lan, X., et al.Inhibition of dopamine receptor D4 impedes autophagic flux, proliferation, and survival of glioblastoma stem cellsCancer Cell29(6)859-873(2016)