Ketonic metabolites of progesterone and 19-norprogesterone in rabbit urine

Abstract

The ketonic fractions of the conjugated metabolites in urine of rabbits treated with progesterone and 19-norprogesterone have been examined. The occurrence of 20[alpha]-hydroxypregn-4-en-3-one as a metabolite of exogenously administered progesterone, together with the absence of 3-[alpha]hydroxy-5[beta]-pregnan-20-one, suggests that the catabolic pathway leading to 5[beta]-pregnane-3[alpha]-20[alpha]-diol is different in the rabbit from that in the human. 20[alpha]-Hydroxy-19-norpregn-4-en-3-one has been identified as a metabolite of 19-nor-progesterone. The former compounds and its 20[beta]-epimer have been synthesized.