ATF3 and acute kidney injury: However, the urine ATF3 in the AKI group was markedly higher than in the non-AKI group at 6 h postoperatively (974.92 ± 341.42 pg/mL vs 1169.90 ± 280.93 pg/mL, P = 0.01), and this significant difference was also observed at 12 h postoperatively (993.23 ± 291.16 pg/mL vs 1190.05 ± 309.58 pg/mL, P = 0.002) (Table 1).