Identification of 20 β-Hydroxyhydrocortisone in Rat Plasma After Administration of Hydrocortisone

Summary (1) After intravenous administration to rats, hydrocortisone-4-C14 was rapidly converted into several more polar compounds, detected by paper chromatographic methods combined with radioautog-raphy. (2) Evidence suggests that the most abundant of these is 20β-hydroxyhydrocorti-sone (Reichstein's Compound E). (3) An authentic specimen of this compound was found to be glycogenic in adrenalectomized mice but to be less active than hydrocortisone. The authentic compound corresponded in activity with the material isolated from rat blood.