Enzyme immunoassay for the measurement of 17α-estradiol 17-N-acetylglucosaminide in rabbit urine
摘要:
17 alpha-estradiol 17-N-acetylglucosaminide (17 alpha E-2 17NAG) is an estrogen metabolite hitherto obtained only in rabbits. To gain insight into this unique conjugate, an enzyme immunoassay (EIA) was established by using antiserum elicited against 3-[3-(1-carboxypropyl)] ether of 17 alpha E-2 17NAG-bovine serum albumin conjugate; horseradish peroxidase, as a label; and 3,3',5,5' -tetramethylbenzidine, as a chromogen. The method proved to be specific, and the detection range of the assay was 0.20-10.00 ng/ml. A proposed double conjugate, 3-glucuronide of 17 alpha E-2 17NAG, was synthesized to validate the EIA. The EIA was applied to the determination of the urinary level of 17 alpha E-2 17NAG in male and female (pregnant and non-pregnant) rabbits with and without beta-glucuronidase-sulfatase preparation from Helix pomatia. The results showed that 17 alpha E-2 17NAG was mainly excreted as a double conjugate (17 alpha E-2 17NAG 3-glucuronide and/or 3-sulfate) and that its level varies during pregnancy. (C) 1999 Elsevier Science Inc. All rights reserved.