Hormonal Regulation of Phosphoenolpyruvate Carboxykinase in Cultured Foetal Hepatocytes from the Rat (original) (raw)

The involvement of glucocorticoids and insulin in the induction of cytosolic Ppyruvate carboxykinase was studied in cultured hepatocytes derived from 19-day foetal rat liver. Dexamethasone did not increase Ppyruvate carboxykinase activity, but had a synergistic effect on the induction of the enzyme by N 6 , 0 2'-dibutyryladenosine 3',5'-monophosphate (BbcAMP). Insulin partially inhibited the induction of Ppyruvate carboxykinase by glucagon, epinephrine or BtZcAMP. The inhibitory effect of insulin was dose-dependent : significant inhibition was obtained with 0.1 nM insulin. However, the effect of insulin was independent of the dose of glucagon or epinephrine added to the culture medium.