Role of dopamine in the regulation of aldosterone and 18-hydroxycorticosterone secretion in man.

This study was designed to investigate dopaminergic mechanisms involved in the control of corticosteroid secretion. Administration of the dopamine agonist bromocriptine (2.5 mg three times a day for 4 days) to 10 normal males suppressed (p less than 0.01) plasma 18-hydroxycorticosterone (18-OHB) responses to upright posture, isometric handgrip exercise, furosemide administration and angiotensin II infusion without altering supine blood pressure, electrolytes or plasma cortisol. Plasma 18-OHB responses to adrenocorticotropic hormone infusion were not altered by bromocriptine treatment. These observations suggest that angiotensin-mediated 18-OHB and aldosterone secretion is selectively inhibited by dopaminergic mechanisms. Thus, dopamine and angiotensin II may operate as opposing factors in the control of aldosterone biosynthesis.