Prostaglandin E2 and the renin-angiotensin system in primary aldosteronism and Cushing's syndrome.

8 patients with primary aldosteronism (PA) and 4 women with Cushing's syndrome (CS) were investigated with estimations of prostaglandin E2 (PGE2), plasma renin activity (PRA), and angiotensin-II (A-II) concentrations in renal venous blood, under resting and strictly standardized conditions and without pharmacological influence. In the PA group all hormone values were extremely low, but with a tendency to higher PRA and A-II concentrations in patients with idiopathic adrenal hyperplasia. Such low PGE2 concentrations have not previously been reported, and may be the consequence of decreased concentration of circulating A-II. However, a yet unidentified mechanism for the parallel suppression of the renin-angiotensin system (RAS) and of products of arachidonic acid metabolism cannot be excluded in hypertensive states where blood pressure is mainly dependent on volume factors. The number of patients in the CS group was too small to permit definitive conclusions, but a specific pattern of the PGE2 production is probably not seen in conjunction with hypercorticism. There seemed to exist only a covariation between PGE2 concentration and the degree of activation of the RAS.