par Hendeles, Salomon ;Galand, Nicole ;Schwers, Jean
Référence Acta endocrinologica (Print ed.), 71, 3, page (557-568)
Publication Publié, 1972-11
Article révisé par les pairs
Résumé : Tritiated D-norgestrel was administered orally to five women. Urine and plasma were collected for 4 days.In plasma the maximum tritium concentration is reached after 4 or 6 hours. This peak represents 0.2 to 0.4 per cent of the administered dose per 100 ml of plasma. After the first 24 hours more than 85 per cent of the radioactivity is in a conjugated form. The half-life of tritium in the plasma, calculated from the values obtained after the first day, varies from 27 to 55 hours.In urine 41 to 67 per cent of the administered dose is excreted within four days, half of this during the first 24 hours. The half-life calculated from the urinary excretion of tritium is 21 hours. As much as 3.6 to 25.7 per cent of the urinary radioactivity is in an unconjugated form. In the conjugated fraction there is evidence which suggests the presence of n-acetylglucosaminides in addition to sulphates and glucuronides. At least ten metabolites of D-norgestrel can be isolated from the urine; all of them, but one, are more polar than the administered material. In one experiment 0.02 per cent of the administered dose was identified as tritiated D-norgestrel.When unlabelled D-norgestrel (0.5 mg per day for 21 days) was administered before the ingestion of the labelled material, no significant change in the metabolic pattern could be observed apart from a possible increase of the half-life of tritium in the plasma.