Abstract
17 beta-N, N-diethylcarbamoyl-4-methyl-4-aza-5 alpha-androstan-3-one (4-MA) inhibits 5 alpha-reductase activity in cultured human genital skin fibroblasts. Enzyme kinetic studies analyzed by Eadie-Hofstee plots demonstrated that 4-MA is a competitive inhibitor, with an apparent Ki of 15 nM. 4-MA had a very low binding affinity for the androgen receptor. When fibroblasts were incubated in the presence of testosterone (T) and 4-MA, nuclear uptake of 5 alpha-dihydrotestosterone (DHT) decreased in parallel with the inhibition of 5 alpha-reductase activity. While the overall sum for the nuclear uptake of T and DHT diminished, the nuclear uptake of T increased. Biological androgen inactivity cannot be precluded on the basis of nuclear T plus DHT uptake.
Original language | English (US) |
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Pages (from-to) | 171-175 |
Number of pages | 5 |
Journal | Journal of Andrology |
Volume | 5 |
Issue number | 3 |
DOIs | |
State | Published - 1984 |
Externally published | Yes |
Keywords
- 5?‐reductase
- androgen receptor
- enzyme inhibitor
- fibroblast
- nuclear uptake
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism
- Reproductive Medicine
- Endocrinology
- Urology