ABSTRACT
The endogenous neutral steroids in adrenal and liver tissue obtained from foetuses of 12–17 weeks gestation were investigated. After extractions, the steroids were fractionated into a monosulphate and a disulphate fraction on Sephadex LH-20. The conjugates were cleaved by solvolysis, and purified on silicic acid and their trimethyl silyl ethers were analysed by gas-liquid chromatography and gas chromatography-mass spectrometry. Only neutral steroid monosulphates were found. The following compounds were identified in the monosulphate fraction of adrenal tissue: dehydroepiandrosterone, 16α-hydroxydehydroepiandrosterone, pregnenolone and 17α-hydroxypregnenolone, and of liver tissue; dehydroepiandrosterone, 16α-hydroxydehydroepiandrosterone, androst-5-ene-3β,16α,17β-triol, pregnenolone, 17α-hydroxypregnenolone and 16α-hydroxypregnenolone. The identifications and the results of the quantitative determinations of endogenous neutral steroid sulphates suggest that pregnenolone is synthesised in vivo in the foetal adrenal and converted to 17α-hydroxypregnenolone and dehydroepiandrosterone sulphates. The latter compound is further transformed to 16α-hydroxydehydroepiandrosterone sulphate. No 16α-hydroxylation of pregnenolone was observed in adrenal tissue, whereas liver tissue seems to form 16α-hydroxypregnenolone. Reduction of a 17-keto group to 17β-hydroxyl and a 20-keto group to 20α-hydroxyl seems to take place in liver but not in adrenal tissue.