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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Characterisation of the affinity of different anabolics and synthetic hormones to the human androgen receptor, human sex hormone binding globulin and to the bovine progestin receptor
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TLDR
The overall results demonstrated that high doses of LNG induce a potent androgen agonistic behavioral effect and that its A-ring reduction diminishes this potency and enables a shift towards a weak estrogen-like effect. Expand
Structural characteristics of anabolic androgenic steroids contributing to binding to the androgen receptor and to their anabolic and androgenic activities Applied modifications in the steroidal structure
TLDR
The structural features of steroids necessary for effective binding to the AR and those which contribute to the stipulation of the androgenic and anabolic activities are presented. Expand
A possible role of progesterone receptor in mouse oocyte in vitro fertilization regulated by norethisterone and its reduced metabolite.
TLDR
It was demonstrated that NET increases the percentage of fertilized oocytes in the same manner as P(4) does, while 5alpha-NET reduces the percentage on the oocyte fertilization process. Expand
Development and standardization of a simple binding assay for the detection of compounds with affinity for the androgen receptor.
TLDR
An AR binding assay is simple and sensitive, avoids the use of animals as a receptor source, and should be of value when screening for endocrine-modulating compounds, whereas in line with previous findings, AR binding properties of dibutylphthalate and its metabolites could not be demonstrated. Expand
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References

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TLDR
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