Effect of Prostaglandin E 1 on the Renin – Aldosterone System in Patients with Diabetic Nephropathy

Abstract

The effect of prostaglandin E₁ (PGE₁) on the renin–aldosterone system was investigated in hospitalized patients with non-insulin-dependent diabetes mellitus presenting with continuous proteinuria but without nephrotic syndrome. Of the 20 patients studied, 10 had continuous positive proteinuria ≥ 200 mg/day and 10 had continuous positive proteinuria < 200 mg/day. Prostaglandin E_l (40 μg in 100 ml normal saline) was infused intravenously over 2 h twice daily for 4 weeks. Plasma renin activity (PRA) and the plasma aldosterone concentration (PAC) were determined by radioimmunoassay at 0 and 120 min after a frusemide injection given before the start of PGE₁ treatment and during administration of PGE₁ in week 4. The patients who had proteinuria < 200 mg/day showed significant decreases in the PRA₀ and the ratio of PRA₁₂₀:PRA₀ and a decrease in the PAC₁₂₀ during prostaglandin PGE₁ administration. When the results for the two patient groups were combined, both the PAC₁₂₀ and the PRA₁₂₀ were found to be significantly lowered during administration of PGE₁. The results indicate that PGE₁ may be valuable in the treatment of diabetic nephropathy, since the compound inhibited the increased reactivity of the renin–aldosterone system in patients with non-insulin-dependent diabetes mellitus.