PROGESTERONE-4-14C AND ITS METABOLITES IN THE BLOOD AFTER INTRAVENOUS INJECTION INTO WOMEN

Abstract

ABSTRACT Progesterone-4-14C was injected intravenously into seven nonpregnant women. The concentration of progesterone-4-14C as well as its free and conjugated metabolites in the blood was studied over a 90 minutes period after the injection. In the free fraction progesterone and small amounts of metabolites, most probably 20α-hydroxy-pregn-4-en-3-one, pregnanediol and pregnanolone were present. In the glucosiduronate fraction, 5β-pregnane-3α,20α-diol, 5β-pregnane-3β,20β-diol and 5β-pregnan-3α-ol-20-one were identified. In small amounts, 5ξ-pregnane-3β,20α-diol, 5ξ-pregnan-3β-ol-20-one and/or 5ξ-pregnan-20ξ-ol-3-one could be detected. From the level of the identified compounds half-life times were calculated. The values obtained were: progesterone 25 and 29 minutes; glucosiduronates 152 and 162 minutes. About 10 minutes after the injection, the concentration of the glucosiduronates was found to be as high as that of progesterone. The concentration of the sulphates was still increasing at the end of the experiments.