Progesterone and oestrogen metabolism in the pregnant marmoset (Callithrix jacchus)

Identification of oestrogen metabolites in human urine by capillary gas chromatography and mass spectrometry

Oestrogen metabolites from the urine of males and pregnant and non-pregnant females were enriched by a procedure involving column chromatography on adsorber resins, gels and ion exchangers, enzymatic solvolysis and extraction, thereby separating the oestrogens from most of the interfering material. After derivatization of the oestrogens as their trimethylsilyl ethers profiles were measured with a fused silica column and a flame ionization detector by gas chromatography. Using a combination of capillary gas chromatography and mass spectrometry approximately 50 oestrogen metabolites were detected in the human urine of males and females, of which 19 were unknown urine compounds. Not all could be identified definitely owing to the lack of reference material. Mass spectra of trimethylsilylated oestrogens with functional groups at position 11 (11-dehydroestradiol, 11-dehydroestrone and 11 beta-hydroxyestrone) were discussed in their common and discernible fragmentations.

Oxidoreductive and hydroxylating metabolism of progesterone in rat liver epithelial cell lines

Mechanisms and sequences of reduction and hydroxylation of progesterone into 6-hydroxypregnanolones were studied in proliferating rat liver epithelial cell cultures. These cell lines had an intense metabolic activity and all the metabolites were unconjugated. The formation of 3 alpha,6 alpha- and 3 beta,6 alpha-dihydroxy-5 alpha-pregnan-20-one was observed when the cells were incubated with progesterone, 5 alpha-pregnane-3,20-dione, 3 alpha- or 3 beta-hydroxy-5 alpha-pregnan-20-one and 6 alpha-hydroxy-5 alpha-pregnane-3,20-dione but not with 6 alpha- or 6 beta-hydroxyprogesterone, 5 beta-pregnane-3,20-dione, 3 alpha- or 3 beta-hydroxy-5 beta-pregnan-20-one. These findings indicate that the potential precursors of the 6 alpha-hydroxypregnanolones have a 5 alpha-configuration. The reduction of 5 alpha-pregnane-3,20-dione at C-3 followed by a 6 alpha-hydroxylation can be postulated as the major, if not the only, metabolic pathway. However, the possibility that 6 alpha-hydroxylation may occur prior to reduction of the C-3 oxo group cannot be entirely ruled out. The stereospecificity of reduction at C-5 and hydroxylation at C-6 are discussed and compared with 6-hydroxylated progesterone metabolites found in man and some other mammals during pregnancy and the neonatal period.