FIGURE 22. Ontogeny of testicular AMH production.

AMH expression is triggered after SOX9 levels increase in the fetal testis. The increase of intratesticular levels of testosterone does not affect AMH expression because fetal Sertoli cells do not express the androgen receptor (AR). After birth the number of Sertoli cells expressing the AR progressively increases. At puberty, when testosterone increases again, AMH production is inhibited.