Preliminary observations on the interaction of domperidone with peripheral dopamine receptors.

Domperidone is a specific dopamine antagonist that does not exert central anti dopaminergic activity in vivo, probably because it does not readily cross the blood brain barrier (Costall et al., 1979; Laduron and Leysen, 1979). In this study, domperidone has been compared with haloperidol in three different experimental situations where dopamine and/ or apomorphine are known to act: in vivo dopamine-induced ganglionic inhibition (Willems, 1973), in vivo dopamine-induced neurogenic vasodilatation (Willems and Bogaert, 1975) and in vivo apomorphine induced vasodilatation (Buylaert et al., 1977). The experimental observations suggest that these phenomena are due to an interaction of dopamine, or apomorphine, with a peripheral dopamine receptor in the sympathetic ganglia, or at the sympathetic nerve endings. Domperidone and haloperidol are equipotent as antagonists of these effects on peripheral dopamine receptors.