Renin, aldosterone and other mineralocorticoids in hyperkalemic patients with chronic renal failure showing mild azotemia.

The role of the renin-angiotensin system in the control of aldosterone and other mineralocorticoids was studied in 9 hyperkalemic patients with chronic renal failure showing mild azotemia (group I) and 6 normokalemic patients with chronic renal failure showing creatinine clearance similar to that in group I (group II). In group I, the plasma renin activity (PRA) was significantly low and plasma aldosterone (PAC) and 18-hydroxycortisterone (18-OH-B) were also significantly reduced. In group II, PRA was normal or slightly increased, and PAC and 18-OH-B were also normal or slightly increased. Both the PAC and 18-OH-B in group I were stimulated by ACTH and angiotensin II, although the responses were less than those in group II. In 2 patients of group I where PRA moved into the normal range after administration of furosemide, the plasma 18-OH-B and PAC also reached the lower limit of normal. These results suggest that suppression of the renin-angiotensin system is probably related to functional disturbance in the conversion from B to 18-OH-B and/or 18-OH-B to aldosterone in most abnormally hyperkalemic patients with chronic renal failure.