Effect of indomethacin upon the renin--angiotensin system in patients with Bartter's syndrome

This study reports on the influence of indomethacin upon the renin--angiotensin system in three patients with Bartter's syndrome. An analogue of angiotensin II with weak agonistic properties (succinamyl1-val5-phenylglycine-acetate8-angiotensin II) induced a fall of blood pressure and a rise of plasma renin concentration but no change in plasma aldosterone. Pretreatment with indomethacin (75 mg/day) reversed the hypotensive effect of the analogue of angiotensin II and abolished the increase of plasma renin concentration. It is concluded that elevated levels of endogenous angiotensin II are of major importance for the maintenance of blood pressure in patients with Bartter's syndrome. The inhibition of the synthesis of prostaglandins reversed some, though not all, of the metabolic abnormalities in this syndrome.