Can 19-nortestosterone derivatives be aromatized in the liver of adult humans? Are there clinical implications?

@article{Kuhl2007Can1D,
  title={Can 19-nortestosterone derivatives be aromatized in the liver of adult humans? Are there clinical implications?},
  author={Herbert Kuhl and Inka Wiegratz},
  journal={Climacteric},
  year={2007},
  volume={10},
  pages={344 - 353}
}
Context Previous studies in postmenopausal women have demonstrated that, after oral administration of norethisterone, a small proportion of the compound is rapidly converted into ethinylestradiol. The shape of the concentration – time curve suggested that this occurred in the liver. The results were confirmed by in vitro investigations with adult human liver tissue. In 2002, it was shown that, after oral treatment of women with tibolone, aromatization of the compound occurred, resulting in the… Expand
Tibolone is not aromatized in postmenopausal women
  • H. Kloosterboer
  • Medicine
  • Climacteric : the journal of the International Menopause Society
  • 2008
TLDR
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Abstract Tibolone is a synthetic steroid that is prescribed to postmenopausal women for relief of climacteric symptoms and prevention of osteoporosis. It has been reported to be metabolized in aExpand
Tibolone is not converted by human aromatase to 7α-methyl-17α-ethynylestradiol (7α-MEE): Analyses with sensitive bioassays for estrogens and androgens and with LC-MSMS
To exclude that aromatization plays a role in the estrogenic activity of tibolone, we studied the effect tibolone and metabolites on the aromatization of androstenedione and the aromatization ofExpand
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TLDR
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