Sertoli cell conditioned media modulate the androgen biosynthetic pathways in rat Leydig cell primary cultures.

Increasing evidence suggests the presence of local modulators that contribute to testicular function regulation in rats. The seminiferous tubules and Sertoli cell factors influence the steroidogenic activity of Leydig cells. Addition of Sertoli cell conditioned media to primary cultures of adult rat Leydig cells produces in a dose-dependent manner an inhibition of testosterone production with a concomitant decrease in the C21 delta 4-intermediates of the steroidogenic pathway, modifying the C21/C19 ratios in normal cells. The nature and mechanisms of action of this putative modulating activity are currently under study.