Fig. 3.

Immunofluorescence microscopic analysis of iNOS and peroxynitrite in the kidney. a–c Representative immunohistochemical images show that iNOS (green staining) is expressed in the vicinity of the apical membrane (P-gp counterstaining, red) in all segments of the proximal tubule 12 h after LPS⁺ treatment. d, e Formation of 3-nitrotyrosine-protein adducts, a reliable biomarker of peroxynitrite generation, were visible in the cortex in peritubulary capillaries and proximal tubules 12 h after LPS⁺ treatment. f, g Coadministration with aminoguanidine resulted in attenuated formation of 3-nitrotyrosine-protein adducts at 12 h. G glomerulus, asterisks peritubular staining, P proximal tubule, D distal tubule. Original magnification d, f ×200 and a–c, e, g ×400