Domperidone-d₆is intended for use as an internal standard for the quantification of domperidone by GC- or LC-MS. Domperidone is a dopamine D₂receptor antagonist (K_i= 0.3 nM in CHO cells expressing the rat receptor).^1,2It is selective for dopamine D₂over D₃receptors (K_i= 9.5 nM).¹Domperidone (0.5-5 µg/kg) inhibits dipropyl dopamine-induced femoral vasodilation in dogs, indicating dopamine D₂receptor antagonist activity, and has no effect on dopamine-induced vasodilation in the renal vascular bed in dogs when administered at doses up to 5 mg/kg, indicating a lack of activity at dopamine D₁receptors.²Domperidone (0.5 mg/kg) prevents dopamine-induced decreases in gastric antral motility induced by pentagastrin in dogs.³It inhibits apomorphine-induced emesis in dogs (ED₅₀= 0.031 mg/kg, p.o.).⁴Domperidone also increases serum levels of prolactin in male rats.⁵

1.Sokoloff, P., Giros, B., Martres, M.P., et al.Molecular cloning and characterization of a novel dopamine receptor (D3) as a target for neurolepticsNature137(6289)146-151(1990) 2.Kohli, J.D., Glock, D., and Goldberg, L.I.Selective DA2 versus DA1 antagonist activity of domperidone in the peripheryEur. J. Pharmacol.89(1-2)137-141(1983) 3.Bech, K., Hovendal, C.P., and Andersen, D.Effect of dopamine on pentagastrin-stimulated gastric antral motility in dogs with gastric fistulaScand. J. Gastroenterol.17(1)103-107(1982) 4.Niemegeers, C.J.E.Antiemetic specificity of dopamine antagonistsPsychopharmacology (Berl).78(3)210-213(1982) 5.Meltzer, H.Y., Simonovic, M., and So, R.Effects of a series of substituted benzamides on rat prolactin secretion and 3H-spiperone binding to bovine anterior pituitary membranesLife Sci.32(25)2877-2886(1983)