The biliary and urinary metabolites of [3H]17 alpha-ethynylestradiol in women

Xenobiotica. 1983 Jul;13(7):421-31. doi: 10.3109/00498258309052280.


The metabolism of 17 alpha-ethynyl[6,7-3H]estradiol (3H-EE2) (50 micrograms) given orally was studied in two groups of women: (a) six subjects from whom duodenal bile samples were obtained after 4 h by endoscopic aspiration; (b) two subjects with bile-duct (T-tube) drainage. The first group eliminated 16.6 +/- 7.8% (mean +/- S.D.) of the dose in urine over 72 h, the second group 28.6% and 27.5%. Biliary excretion by the latter was 41.9% and 28.3% of the dose, respectively, during the first 24 h after dosing. The metabolites excreted in bile and urine were largely polar conjugates: 1-12% of the 3H was ether extractable. Approx. 70-90% of urinary and biliary 3H was extractable following beta-glucuronidase-arylsulphohydrolase hydrolysis. Both beta-glucuronides and arylsulphates were excreted. Unchanged 3H-EE2 was the principal 3H-labelled component of the glucuronide and arylsulphate fractions of bile, and it was a major component of urinary fractions. 2-Hydroxy-EE2 and 2-methoxy-EE2 were identified as conjugated biliary metabolites.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Arylsulfatases
  • Bile / metabolism*
  • Chromatography, High Pressure Liquid
  • Ethinyl Estradiol / metabolism*
  • Ethinyl Estradiol / urine
  • Female
  • Glucuronates / metabolism
  • Glucuronidase
  • Humans
  • Hydrolysis
  • Kinetics
  • Middle Aged
  • Sulfuric Acid Esters / metabolism
  • Tritium


  • Glucuronates
  • Sulfuric Acid Esters
  • Tritium
  • Ethinyl Estradiol
  • Arylsulfatases
  • Glucuronidase