Randomized controlled trial of ACE-inhibitors and beta-blockers with and without vasodilating activity in chronic glomerulonephritis.

A prospective double-blind, randomized study was conducted to compare the effects of the beta 1 antagonist, beta 2 agonist celiprolol (200 mg daily) on renal hemodynamics and protein excretion with those of the beta 1 antagonist atenolol (50 mg daily), the ACE-inhibitor ramipril (2.5 mg daily), and placebo in 11 patients with proteinuria > 400 mg/24 h due to chronic glomerulonephritis. All 4 substances were given in a double-blind, randomized manner according to a latin-square design over a period of 4 weeks with a wash-out period of 2 weeks in between. Glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were measured by inulin and PAH clearance. Proteinuria was assessed by urine sampling at the end of each treatment period. Mean arterial pressure (MAP) was reduced significantly (p < 0.01) by all 3 drugs compared to placebo (108 +/- 9 mmHg placebo, 98 +/- 12 mmHg atenolol, 101 +/- 11 mmHg celiprolol, and 98 +/- 8 mmHg ramipril). Celiprolol induced a significant increase in ERPF compared to placebo (322 +/- 109 ml/min under placebo versus 391 +/- 110 ml/min under celiprolol, p < 0.05). GFR was slightly but insignificantly increased under atenolol and celiprolol. Filtration fraction (FF) remained unchanged in case of atenolol and celiprolol treatment and was slightly but not significantly reduced by ramipril. Proteinuria was significantly (p < 0.05) reduced compared to placebo by all 3 drugs (1.8 +/- 1.3 g/24 h under placebo, 1.2 +/- 1.2 g/24 h under atenolol, 1.2 +/- 1.1 g/24 h under celiprolol, and 1.4 +/- 1.4 g/24 h under ramipril). These data demonstrate that new beta-blocking agents show favorable effects on proteinuria and renal blood flow in patients with chronic glomerulonephritis and arterial hypertension. This may be attributed to their vasodilating properties.