Glucocorticoids and the isolated rat hepatocyte.

Following incubation at 37 degrees C with tritiated glucocorticoids isolated hepatocytes prepared from non-adrenalectomized rats show rapid uptake of label. Uptake is non-saturable, and non-linear over the first 60 sec of exposure to steroids. HPLC separation of aqueous extracts of cells and incubation medium shows that polar metabolites of the natural steroid, corticosterone, appear within 10 sec, whereas the synthetic glucocorticoid, dexamethasone, is not altered. Our results suggest that diffusion is the most important process by which glucocorticoids enter liver cells, and that the predominant fate of corticosterone is rapid metabolism.