[Do androgens modulate luteinizing hormone secretion in women?]

Area of Science:

• Endocrinology
• Reproductive Biology
• Neuroendocrinology

Context:

• Hyperandrogenic states in women are linked to abnormal luteinizing hormone (LH) secretion patterns.
• This abnormal secretion is thought to stem from androgen action or estrogen conversion.
• Investigating testosterone's direct impact on LH secretion is crucial for understanding these conditions.

Purpose:

• To investigate the role of androgen receptor blockade in modulating LH secretion in hyperandrogenic women.
• To determine the direct effect of testosterone on LH secretion at the pituitary level in patients with hypothalamic deficiency.
• To elucidate the mechanism by which testosterone influences LH secretion and its potential reversal by androgen receptor antagonists.

Summary:

• Flutamide, an androgen receptor blocker, decreased LH pulse amplitude and mean LH concentrations in hyperandrogenic women, indicating androgen receptor blockade reduces LH secretion.
• In patients with hypothalamic deficiency receiving pulsatile gonadotropin-releasing hormone (GnRHp), testosterone administration (at hyperandrogenic levels) increased LH secretion and pulse amplitude.
• Flutamide administration reversed the testosterone-induced increase in LH secretion, suggesting testosterone facilitates pituitary LH secretion, an effect mediated via androgen receptors.

Impact:

• Provides evidence that testosterone directly influences pituitary LH secretion in women with hyperandrogenism.
• Highlights the role of androgen receptors in regulating gonadotropin secretion.
• Offers insights into potential therapeutic targets for managing abnormal LH secretion in hyperandrogenic conditions.