Biosynthesis of Sterols and Steroids from Acetate-14C by Human Fetal Ovaries1

Abstract

Homogenates of human ovaries obtained from fetuses at 20 and 22 weeks of gestational age were incubated with sodium acetate-l-¹⁴C. The extracts were analyzed for sterols and steroids by the reverse isotope dilution technique. Purification and identification of the radioactive metabolites were achieved by paper and thin-layer chromatography, derivative formation and crystallization to constant specific activity. Evidence has been obtained for the formation of lanosterol and cholesterol. Small, but definite quantities of radioactive pregnenolone and progesterone were identified. No evidence was found for the formation of dehydroepiandrosterone, androstenedione, testosterone and estrogens.