The intranuclear binding of 17 beta-hydroxy-5 alpha-androstan-3-one and testosterone by hamster sebaceous glands.

After the administration of 3-H-testosterone to castrated hamsters, extracts from crude nuclei were separated into bound and free fractions by gel filtration of Sephadex G-25, Subsequent analysis by thin-layer chromatography and recrystallization showed that dihydrotestosterone was the predominant radioactive steroid in the bound fraction and that it increased steadily with time until 1 hr after the injection. Further purification of the nuclear fraction showed an abundance of dihydrotestosterone in the nuclei. The binding was significantly decreased by pronase treatment, only slightly affected by deoxyribonuclease, and remained unaffected by ribonuclease. From the elution pattern on Sephadex G-200, the molecular weight of the binding macromolecule was estimated to be 3 times 10-4 daltons.