Arterial hypertension in acromegaly: altered dopaminergic control of aldosterone secretion

In order to elucidate the role of the dopaminergic system in the control of aldosterone secretion in acromegaly with arterial hypertension 10 patients and 10 healthy volunteers were studied. Plasma aldosterone and prolactin were determined by radioimmunological methods after dopaminergic receptor blockade with metoclopramide and sulpiride. Plasma aldosterone was also determined after adrenal stimulation with synthetic corticotrophin (Synacthen). In patients with acromegaly and hypertension, the aldosterone secretion in response to metoclopramide was completely inhibited whereas induced with corticotrophin was lower than in controls. Also prolactin secretion in response to metoclopramide or sulpiride was markedly lower as compared with that in controls. Sulpiride did not stimulate aldosterone secretion either in patients or in healthy controls. The results indicate that the dopaminergic control of aldosterone secretion in acromegaly with arterial hypertension is altered.