5α-Reduction of norethisterone enhances its binding affinity for androgen receptors but diminishes its androgenic potency

@article{Lemus19975ReductionON,
  title={5$\alpha$-Reduction of norethisterone enhances its binding affinity for androgen receptors but diminishes its androgenic potency},
  author={A. E. Lemus and J. Enr{\'i}quez and G. Garc{\'i}a and I. Grillasca and G. P{\'e}rez-palacios},
  journal={The Journal of Steroid Biochemistry and Molecular Biology},
  year={1997},
  volume={60},
  pages={121-129}
}
Norethisterone (NET), a 19-nor synthetic progestin, undergoes enzyme-mediated 5alpha-reduction and exerts potent androgenic effects in target organs. To investigate its mode of androgenic action we examined, in a comparative manner, the in vitro metabolism of NET and testosterone (T), as well as the binding affinities to androgen receptors (AR) and the androgenic potency of NET, T, and their 5alpha-reduced derivatives. Bioconversion of [3H]-NET and [3H]-T was studied in rat prostate homogenates… Expand
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