Immunostaining for nitrotyrosine (NT). Representative nitrotyrosine staining in the kidneys of rats .In the control rat nitrotyrosine staining was minimal. In TDF treated rat kidney cortex, both proximal convoluted tubule (PCT) and distal convoluted tubules (DCT) stained strongly for NT. The glomerulus (G) showed mild staining for NT. In the medulla, loop of Henle and collecting tubules (CoT) stained for NT (X40).