Figure 9.

Potential interrelation between AngII and ET-1 in tubulointerstitial nephritis. Persistent intense proteinuria may cause an overproduction of AngII and ET-1 in proximal tubular cells, and both peptides, directly or through the induction of each other, may participate in the tubulointerstitial injury in this model. AT1(−/−) animals and WT treated with the ACE inhibitor quinapril had less renal damage probably because of the interference with pathway 1, and pathways 1 and 2, respectively. The beneficial effect of the ETA/ETB antagonist bosentan could be because of the blockade of pathways 2 and 3. The combined therapy of quinapril and bosentan may afford a synergistic effect because they block the pathways 1, 2, and 3.