Additive antiproteinuric effect of angiotensin IIreceptor antagonist and angiotensin-converting enzyme inhibitor in patients with chronic glomerulonephritis

Abstract

Angiotensin II type-1 receptor blocker (ARB) and angiotensin-converting enzyme inhibitor (ACEI) have been thought to be effective for reducing proteinuria in patients with chronic glomerulonephritis. Recently, an additive effect of these two types of angiotensin blockers has been reported in patients with 1gA nephropathy, but the mechanism responsible for the effect has not yet been determined. In this study, we examined additive effect of these two drugs in chronic glomerulonephritis patients. Ten patients with biopsyproven primary glomerulonephritis (eight IgA nephropathy patients, two membranous nephropathy patients), non-nephrotic proteinuria (protein, 0.5 to 3.5 g/day) received candesartan cilexetil (2 or 4 mg) for 8 weeks. After the 8 weeks, a combination of perindopril erbumine (l or 2 mg) and candesartan cilexetil was administered to the patients. Perindopril was stopped after the 8-week administration of the two drugs. Candesartan alone reduced proteinuria by 13 %. Combination of these two drugs induced a more remarkable reduction of proteinuria(48 % ; p<0.05 vs other periods). The decrease in mean blood pressure by the combination therapy was significantly correlated with the decrease in proteinuria. The combination of drugs also reduced the amount of urinary type IV collagen excretion. An additive effect of ACEI and ARB on proteinuria and urinary type IV collagen excretion was recognized in patients with chronic glomerulonephritis.