Table 1

Competition binding conditions at recombinant, human dopaminereceptors

ReceptorTissueRadioligand (nM)Buffer (mM)pHNonspecific (μM)Time, temperatureKd
(nM)
hD1 L cells[3H]SCH23390 (0.3)Tris-HCl (50), NaCl (120), KCl (5), CaCl2 (2), MgCl2(5)7.4(+)Butaclamol (3)60 min, 25°C0.53
hD2S CHO cells[125I]iodosulpride (0.1)Tris-HCl (50), NaCl (120), KCl (5), CaCl2 (2), MgCl2(5)7.4Raclopride (10)30 min, 22°C0.45
hD2L CHO cells[125]iodosulpride (0.1)Tris-HCl (50), NaCl (120), KCl (5), CaCl2 (2), MgCl2 (5)7.4Raclopride (10)30 min, 22°C0.45
hD3 CHO cells[125I]iodosulpride (0.2)Tris-HCl (50), NaCl (120), KCl (5), CaCl2 (2), MgCl2 (5)7.4Raclopride (10)30 min, 22°C0.98
hD4 1-a CHO cells[3H]spiperone (0.5)Tris-HCl (50), NaCl (120), KCl (5), MgCl2 (5), EDTA (1)7.4Haloperidol (1)60 min, 22°C0.38
hD5 CH4Cl cells[3H]SCH23390 (0.3)Tris-HCl (50), NaCl (120), KCl (5), MgCl2 (5), EDTA (1)7.4SCH23390 (10)60 min, 22°C0.25
  • CHO, Chinese hamster ovary.

  • 1-a h4.4. isoform.