Figure 10.

Putative pathways of androgen action on preantral follicle growth. Testosterone (T) or DHT act via the AR, causing a measurable increase in GC proliferation. This may be mediated directly, or indirectly, by increased FSHR (stimulating GC proliferation) or decreased AMH (reducing AMH inhibition). AMH can be further reduced by androgen-induced reduction of oocyte-specific BMP, which normally stimulates AMH levels. Inset box summarizes androgen-induced inhibition of TGFβ ligands and type I and II TGFβ receptors, with the exception of Alk6.