We evaluated if the blockade of the proinflammatory transcription factor NF-B would modify the oxidative stress, the inflammation and the structural and hemodynamic alterations found in the kidney as a result of massive proteinuria. Twenty male Sprague-Dawley rats were injected with 2 grams of bovine serum albumin (BSA) intraperitoneally daily for 2 weeks. Ten of them received in addition the inhibitor of NF-B activation pyrrolidine dithiocarbamate (PDTC) (200 mg.kg-1.day-1 subcutaneously) and the rest received vehicle. Seven rats that received intraperitoneal saline were used as controls. Glomerular hemodynamics was studied after 14 days. Markers of oxidative stress [NF-B subunit p65+ cells, 3-nitrotyrosine (3-NT) and 4- hydroxynonenal (4-HNE)], inflammation (cortical CD68+ cells and NOS-II) and afferent arteriole damage were assessed by immunohistochemistry and morphometry. Activity of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione reductase (GR) were evaluated in renal cortex and medulla. Albumin overload (AO) induced massive proteinuria, oxidative stress with reduced activity of antioxidant enzymes, NF-B activation, inflammatory cell infiltration, a significant presence of proteinaceous casts, systemic and glomerular hypertension, as well as arteriolar remodeling. Treatment with PDTC prevented or improved all of these findings. In this model of nephrotic syndrome we demonstrate a key role for oxidative stress and inflammation in causing systemic and glomerular hypertension and proteinuria. Oxidative stress and inflammation may have a key role in accelerating renal injury associated with intense proteinuria.