1993/06/25 by T.M. Yalcinkaya, Pentti K. Siiteri, Jean‐Louis Vigne +4 · 2 citations
Psychology · Medicine · #Neuroendocrine regulation and behavior #Sperm and Testicular Function #Evolutionary Psychology and Human Behavior #Androstenedione #Virilization #Internal medicine #Endocrinology #Hyena #Aromatase #Testosterone (patch) #Biology #Androgen #Flutamide #Hormone #Medicine #Zoology #Androgen receptor
paper · doi:10.1126/science.8391165
openalex publication_date 1993/06/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Female spotted hyenas exhibit male-like genitalia and dominance over males. Hyena ovarian tissues incubated in vitro produced large quantities of the steroid hormone precursor androstenedione. The activity of aromatase, which converts androstenedione to estrogen, was one-twentieth as great in hyena versus human placental homogenates. In comparison, the activity of 17 beta-hydroxysteroid dehydrogenase, which converts androstenedione to testosterone, was equal in the two homogenates. The limited aromatase activity may allow the hyena placenta to convert high circulating concentrations of androstenedione to testosterone, which results in virilization of the fetal external genitalia and possibly destruction of fetal ovarian follicles. Androstenedione production by residual ovarian stromal cells during reproductive life accounts for the epigenetic transmission of virilization in female spotted hyenas.