Effects of betamethasone 17, 21-dipropionate on activities of glycogen synthase and tyrosine aminotransferase in fetal rat liver in organ culture

Abstract

Betamethasone 17, 21-dipropionate (BDP) does not have glycogenic activity and antagonizes cortisol in glycogenesis in fetal rat liver explants. In an attempt to elucidate whether BDP commonly has an antagonistic effect on the glucocorticoid responsive system in fetal rat liver, effects on activities of glycogen synthase and tyrosine aminotransferase were examined. Cortisol increased both total and α activities of glycogen synthase at concentrations above 3×10^-8M. BDP, unlike cortisol, did not increase total synthase activity at 10^-6M and antagonized cortisol (10^-6M), but like cortisol, it did increase synthase α activity. Both cortisol and BDP increased tyrosine aminotransferase activity at concentrations above 10^-8M. BDP did not always act as an antagonist in the glucocorticoid responsive systems in fetal rat liver.