Identification of 16-dehydropregnenolone as an intermediate in 16-androstene biosynthesis in neonatal porcine testicular microsomes.

The biosynthesis of 16-androstenes has been studied in neonatal porcine testicular microsomes using 17-hydroxypregnenolone and 16-dehydropregnenolone, separately, as substrates. The metabolites formed after microsomal incubation with these substrates were purified, derivatized as O-methyloxime-trimethylsilyl ethers and analysed by capillary gas chromatography-mass spectrometry. In the incubation of 17-hydroxypregnenolone with microsomes, 16-dehydropregnenolone was identified as an intermediate in the biosynthesis of 16-androstenes. Further microsomal incubation of 16-dehydropregnenolone has established the intermediary role of this steroid in the production of 16-androstenes.