2.7. Measurement of Caspase-3 Activity

Caspase-3 activity in the mice kidney and MDCK cells was measured using a colorimetric assay kit (Sigma-Aldrich) in accordance with the manufacturer’s protocol. In brief, kidney homogenates were incubated with the fluorometric caspase-3 substrate, Ac-DEVD-pNA, in the assay buffer. To account for nonspecific hydrolysis of the substrate, a control reaction mixture containing the caspase-3 inhibitor, acetyl-DEVD-CHO, in the assay buffer was used. Both mixtures were incubated for 90 min at 37 °C, with the absorbance being read at 405 nm.