Influence of androgens and age on androgen receptor and 5 alpha-reductase II transcription

Objective: The regulation of the androgen receptor (AR) and 5 alpha-reducta se IT (5RII) gene in genital skin fibroblasts is of particular interest in understanding androgen-dependent embryonic formation of external male genit alia, Design: Human genital skin fibroblasts from pre- and postpubertal male indi viduals (aged 5 months to 51 years) were incubated with testosterone and di hydrotestosterone under various conditions to study the regulation of AR an d 5RII transcript concentrations dependent on androgen concentration and do nor age, Methods: A competitive reverse transcribed PCR (RT-PCR) protocol was design ed to achieve simultaneous relative quantification (semi-quantification) of AR and 5RII mRNAs in standardized whole RNA samples from each donor. Results: Concentrations of AR and 5RII mRNAs are not influenced by androgen s in genital skin fibroblasts, Moreover, comparison of AR transcript concen trations in genital skin fibroblast cell lines revealed weak variations ind ependent of donor age, while 5RII transcription exhibited clear individual differences with a declining tendency towards higher ages. Conclusions: The transcription of AR and 5RII is not directly regulated by testosterone or dihydrotestosterone in pre- or postpubertal human genital s kin fibroblasts. However, donor age seems to play a role in gradual depress ion of 5RII transcription.