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International Urology and Nephrology

, Volume 24, Issue 2, pp 145–154 | Cite as

In vitro study of rat prostate 5α-reductase activity and its inhibition

  • I. Faredin
  • I. Tóth
  • J. Oszlánczy
  • S. Scultéty
Article

Abstract

A simple and rapid method of measuring 5α-reductase (5α-R) activity and of determining the kinetic parameters (KM and Vmax) of the enzyme is described. The 5α-R activity in the homogenate of the prostate of Wistar rats aged 8–12 weeks was established, and the effects of natural and synthetic steroids and of non-steroidal antiandrogens (IC50) upon the 5α-R activity were studied. Of the natural steroids, 17-0H-progesterone was found to have the highest inhibitory effect (IC50=1.35 μM), followed in decreasing order by progesterone (IC50=5.0 μM) and 4-androstene-3,17-dione (IC50=21.6 μM). Oestradiol-17β had practically no inhibitory effect. Of the synthetic steroids, 4-MA had the highest inhibitory effect (IC50=0.068 μM), followed by nortestosterone (IC50=7.4 μM) and RU-486 (Mifepristone) (IC50=115 μM). Even at 1000 μM, cyproterone acetate exerted no inhibitory effect. Of the nonsteroidal compounds, ketoconazole proved a weak inhibitor (IC50=115 μM), while flutamide was practically ineffective.

Keywords

Testosterone International Urology Flutamide Mifepristone Cyproterone Acetate 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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Copyright information

© Akadémiai Kiadó 1992

Authors and Affiliations

  • I. Faredin
    • 1
  • I. Tóth
    • 1
  • J. Oszlánczy
    • 2
  • S. Scultéty
    • 2
  1. 1.Endocrine Unit, First Department of MedicineSzent-Györgyi Albert Medical UniversitySzegedHungary
  2. 2.Department of UrologySzent-Györgyi Albert Medical UniversitySzegedHungary

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