De novo synthesis of steroids (from acetate) by isolated rat Sertoli cells

Sertoli cells from 17 day old rats were shown to convert [14C]acetate to [14C]-labelled cholesterol, pregnenolone and 17α-hydroxypregnenoloneinvitro. Identification was by several systems of thin layer and gas chromatography of the extracted steroids and their sylil and acetyl derivatives and by recrystallizations with authentic and acetylated unlabelled steroids. Several other steroids formed from acetate were tentatively identified. No androstenedione or testosterone were formed. That the Sertoli cell cultures were free of Leydig cells was established by the absence of histochemically detectable 3β-hydroxysteroid dehydrogenase activity and the inability of the cultures to oxidize the 3β-hydroxyl group of [14C]pregnenolone. This is the first direct evidence that Sertoli cells have the capacity to synthesize steroids denovo from acetate.