Steroid metabolism in guinea pigs. I. Metabolism of cortisol in vivo.

In previous studies (l-3) cortisol (hydrocortisone) was isolated and identified from the urine of the normal and the scorbutic guinea pig. However, paper partition chromatography of extracts of guinea pig urine (2) revealed that in addition to cortisol several other blue tetrazolium-reducing steroids were present. The possibility existed that some of these steroids were metabolites of endogenous cortisol, and it was believed that an understanding of the metabolic pathways operating in this animal would aid in the evaluation of corticosteroid excretion patterns under normal and pathological conditions. The study of the metabolism of cortisol in this animal therefore was undertaken.