NTN1 and acute kidney injury: A study of cardiopulmonary bypass (CPB)-associated AKI found that urinary netrin-1 increased 2 h after CPB, peaked at 6 h (2462 ± 370 pg/mg creatinine) and continued to increase up to 48 h after CPB, whereas the increase of creatinine was detected only after 48 h [67].