Urinary excretion of ulinastatin and NAG after cardiopulmonary bypass

Although urinary trypsin inhibitor (ulinastatin, UTI) is excreted into urine, its physiological function has not been clarified well. Administration of UTI during surgical procedure was reported to protect renal function from surgical stress. This result suggests participation of UTI excretion in renal tubular function. In this study, the amount of urinary excretion of UTI and that of N-acetyl-beta-D-glucosaminidase (NAG) after cardiopulmonary bypass (CPB) were measured. The urinary UTI excretion increased after surgery and reached the maximum on the third postoperative day. NAG also increased gradually and was three times greater than control on the seventh postoperative day. There was a good correlation between NAG and UTI on the first postoperative day. It is suggested that UTI might correlate with the renal tubular function after CPB.