Metabolism of steroids by mouse teratocarcinoma cells

Abstract

Steroid metabolism was studied in cells of a pluripotent mouse teratocarcinoma (TC) line OC15S1. One to five day old monolayer cultures were incubated for 3 to 20h in the presence of radioactive pregnenolone, progesterone, dehydroepiandrosterone (DHA), androstenedione or estradiol-17β. Extracted radioactivity was analyzed by thin layer chromatography, gas liquid chromatography and recrystallizations to constant specific activity and constant isotope ratio. The substrates were metabolized to different extents and most of the metabolites were excreted into the medium. The age of the culture did not affect the results. Similar types of metabolic conversion of steroids was obtained by cultured mouse embryonic fibroblasts which were used as a reference. The results indicated that the cultured TC cells are not capable of 1. efficient conversion of pregnenolone to progesterone nor of 2. significant modification of the major exogenous estrogen, estradiol-17β, but are capable of 3. efficient modification of progesterone and of 4. converting pregnenolone to a more polar form, as well as of 5. metabolizing both DHA and androstenedione.