Glucocorticoid hormones increase the activity of gamma-glutamyltransferase in a highly differentiated hepatoma cell line.

Gamma-Glutamyltransferase activity was detected in the plasma membrane of the highly differentiated hepatoma cell line Fao, (0.93 mU/mg cell protein). Dexamethasone (1 microM) provoked a 2-3-fold increase in the activity of the enzyme in the presence of fetal calf serum.

Physiological and physiopathological modulations of the balance between alpha- and beta-adrenoreceptors.

Adrenergic receptors exist as two subtypes, alpha, and beta, in various tissues. In rat liver, catecholamines exert the same effect on glycogenolysis and neoglucogenesis via either alpha or beta control. In this review we report on the modification in the balance between alpha- and beta-adrenoreceptors induced as the result of adrenalectomy and extrahepatic cholestasis.