PLASMA-ALDOSTERONE RESPONSE TO METOCLOPRAMIDE IN PATIENTS WITH CUSHINGS-DISEASE

The acute effect of metoclopramide on aldosterone and prolactin levels were studied in 8 control subjects and 11 patients with Cushing's dis ease. Metoclopramide (10 mg i.v.) induced a similar plasma prolactin r esponse in control subjects and patients. No difference was found in b asal aldosterone levels between the two groups. Apart from a more dela yed aldosterone response to metoclopramide in the Cushing's disease gr oup, no significant difference in the peak aldosterone values was foun d between the patients and controls. The short-term treatment with DA2 -receptor agonist bromocriptine was without effect on aldosterone resp onse to metoclopramide in the Cushing's disease group. These results a rgue against an altered dopaminergic control of aldosterone secretion in patients with Cushing's disease. The lack of a bromocriptine effect on aldosterone response to metoclopramide is in accordance with the c oncept that the dopamine receptors involved in aldosterone regulation differ from classical DA2 receptors.