There is clear evidence that pharmacologic blockade of the renin-angiotensin system (RAS) with angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB) reduces proteinuria and slows the progression of renal disease in diabetic and nondiabetic nephropathies, a beneficial effect that is not related to BP control. Some patients exhibit a significant beneficial response, whereas others do not. The absence of response may be explained by the incomplete blockade of the RAS obtained with ACEI. In the search of new alternatives that could improve the antiproteinuric and nephroprotective effects of RAS blockers, the association of ACEI and ARB might prove useful. ARB produces a complete blockade of the RAS. Several studies have shown a more marked antiproteinuric effect of the dual blockade of the RAS versus ACEI or ARB alone. A recent study also demonstrated that this more marked antiproteinuric effect is associated with less progression of renal disease in primary nondiabetic nephropathies despite a similar effect on BP. Until now, there has not been any reference to a beneficial effect on progression of the dual blockade in type 2 diabetic nephropathy, which is the most frequent cause of ESRD. A multicenter, prospective, open, active-controlled, and parallel-group trial was designed to compare the effects of an ACE inhibitor versus an ARB or its combination on renal disease progression, proteinuria, and cardiovascular events in type 2 diabetic nephropathy. S ingle-nephron hyperfiltration hypothesis, put forward by Brenner more than 20 yr ago, helped to explain the inexorable decline in renal function that is observed in chronic renal disease once the initial insult has disappeared. Angiotensin II is responsible for the increase in glomerular hydraulic capillary pressure by means of increasing systemic BP along with vasoconstriction of the efferent arteriole, thereby increasing filtration pressure in glomerular capillary walls. In experimental rat models with renal disease, a decrease of similar magnitude in systemic BP can be achieved either with angiotensin-converting enzyme inhibitors (ACEI) or with a combination of diuretics, reserpine and hydralazine, although only in those who are treated with ACEI is a reduction in glomerular capillary pressure and in progression of renal disease observed (1).
J Am Soc NephrolBesides these hemodynamic changes, many other experimental models of renal damage that result in severe proteinuria (e.g., nephrosis by adriamycin or immune-complex glomerulonephritis [2,3]) have implicated angiotensin as a mediator in most of the inflammatory mechanisms that are involved in the progression of chronic renal disease. In proteinuric nephropathies, protein trafficking through proximal tubular cells, besides damaging this tubular segment, stimulates the production of NF-B, in part induced by angiotensin (4). NF-B is present in all cellular types and plays a crucial role in inflammation and apoptosis. In experimental models of nephritis, activation of NF-B results i...