Malis F, Fric E K, Korbová L
J Clin Chem Clin Biochem. 1976 Oct;14(10):499-500.
After a single dose of up to 50 mg/kg body weight (optimal amount for the test) of p-aminobenzoic acid or the corresponding amount of synthetic chymotrypsin substrate N-acetyl-L-tyrosyl-p-aminobenzoic acid, the urinary excretion of p-aminobenzoic acid in rats increases approximately linearly during 24 h. Higher doses do not cause any further significant increase in the amount of urine excreted p-aminobenzoic acid. Compared with a 24 h collecting period, 82% of p-aminobenzoic acid and 77% of p-aminobenzoic acid from N-acetyl-L-tyrosyl-p-aminobenzoic acid were excreted in the urine during the first 6 h after oral application of these substances. Therefore it is sufficient for practical purposes to determine p-aminobenzoic acid in 6 h urine samples. Stimulation of pancreatic secretion by application of 2.5 U of pancreozymin and 2.5 U of secretin failed to bring about significant increase in the cleaved p-aminobenzoic acid in the urine.
给大鼠单次服用高达50毫克/千克体重（测试的最佳剂量）的对氨基苯甲酸或相应量的合成胰凝乳蛋白酶底物N-乙酰-L-酪氨酰-对氨基苯甲酸后，大鼠尿中对氨基苯甲酸的排泄量在24小时内近似呈线性增加。更高剂量不会导致尿中排泄的对氨基苯甲酸量进一步显著增加。与24小时收集期相比，口服这些物质后的前6小时内，尿中82%的对氨基苯甲酸和77%来自N-乙酰-L-酪氨酰-对氨基苯甲酸的对氨基苯甲酸被排泄出来。因此，出于实际目的，测定6小时尿样中的对氨基苯甲酸就足够了。通过应用2.5单位的促胰液素和2.5单位的促胰酶素刺激胰腺分泌，未能使尿中裂解的对氨基苯甲酸显著增加。
