Effect of domperidone, an extracerebral inhibitor of dopamine receptors, on thyrotropin, prolactin, renin, aldosterone, and 18-hydroxycorticosterone secretion in man.

This study investigates the dopaminergic mechanisms involved in the control of corticosteroid secretion in normal subjects. TSH, PRL, PRA, aldosterone, and 18-hydroxycorticosterone (18-OHB) were measured before and after the administration of domperidone (10 mg, iv) to eight healthy males. Domperidone, a selective peripheral dopamine antagonist, stimulated TSH and PRL secretion. Plasma concentrations of aldosterone, 18-OHB, cortisol, and PRA were not altered by domperidone. This is in contrast to previous observations of aldosterone, 18-OHB, and PRA responses to metoclopramide, a dopamine antagonist which readily crosses the blood-brain barrier. Domperidone may fail to stimulate aldosterone, 18-OHB, and renin secretion because it does not cross the blood-brain barrier or does not function as an antagonist for adrenal dopamine receptors modulating 18-OHB and aldosterone secretion.