摘要NBT-PABA test was performed in 72 subjects with simultaneous determination of the plasma PABA time-concentration curve. The curve in 25 controls after oral administration of N-benzoyl-L-tyrosyl-P-aminobenzoic acid (NBT-PABA) peaked (3.88±0.78μg/ml, M±SD) at the third hour. In patients with chronic pancreatitis (24) and pancreatic carcinoma (6), the curves were flattened, and peaked at the fifth hour (2.7±1.4pg/ml, M±SD), and fourth hour (3.14±2.26pg/ml, M±SD), respectively. The discrimination between the controls and patients with chronic pancreatitis was most significant in the third-hour plasma PABA concentration (P<0.0001). This study shows that determination of the third-hour plasma PABA concentration is better in sensitivity and specificity than the 6-hour urinary excretion of PABA, suggesting that the third-hour plasma PABA concentration after oral administration of NBT-PABA might be a sensitive index of exocrine pancreatic function test.