Renal damage progresses despite improvement of renal function after relief of unilateral ureteral obstruction in adult rats

Progression of renal damage after relief of unilateral ureteral obstruction (UUO) has been demonstrated, especially in neonatal rats. We evaluated renal function and renal damage after relief of 3-day UUO in five groups of adult rats: group 1, no treatment; group 2, 3-day UUO; groups 3-5, 3-day UUO followed by relief; group 3, 7-day relief; group 4, 14-day relief; and group 5, 28-day relief. Glomerular filtration rate (GFR), renal blood flow (RBF), tissue transforming growth factor-[beta] (TGF-[beta]), interstitial fibrosis and fibroblast expression, tubular apoptosis, macrophage infiltration, expression of nitric oxide synthases (NOS), and urinary nitrate/nitrite (N[O.sub.2]/N[O.sub.3]) were evaluated. RBF and GFR were decreased to Sprague-Dawley rats; interstitial fibrosis; apoptosis; transforming growth factor-[beta]; FSP; nitric oxide