Fig. 2

Irradiation-induced cellular apoptosis in kidney tissues. a, b Irradiated kidney tissues collected at days 1, 3 and 7 (d1, d3, d7) after total body irradiation (TBI). TUNEL staining used to detect cellular apoptosis. Representative pictures by TUNEL staining (a). Bar = 50 μm. Ratio of apoptotic cells (arrowed) in each field (b). c, d Irradiated kidney tissues collected at days 1, 3 and 7 after TBI. Cellular cleaved caspase-3 determined by immunostaining. Representative pictures by cleaved caspase-3 staining (c). Bar = 50 μm. Imaging software used to analyze integrated optical density (IOD) of cleaved caspase-3 (d). e, f BrdU incorporation assay in kidney tissues. BrdU (100 mg/kg) intraperitoneally injected 2 h before mice were euthanized. BrdU-positive cells (e, arrowed) counted under light microscope and percentages of BrdU-positive cells in each field presented (f). Bar = 100 μm. ***p < 0.001 vs CTL. CTL nonirradiated renal tissues, N.D nondetected