Hydrocortisone-induced changes in hepatic glucose-6-phosphatase and fructose diphosphatase activities

Abstract

The marked increases in hepatic glucose-6-phosphatase and fructose diphosphatase activities observed after hydrocortisone administration in adrenalectomized rats is inhibited by treating the animals with the methionine antagonist, ethionine. This inhibition is, in turn, reversed by the administration of methionine. This is further evidence that these increases represent adaptive enzyme formation involving the synthesis of new protein. In the presence of ethionine both blood sugar and hepatic glycogen levels rise after hydrocortisone injection but to values distinctly below those found when adaptive enzyme formation can occur. Ethionine treatment does not affect the rate at which blood sugar and hepatic glycogen concentrations increase for the first 6–12 hours after glucocorticoid injection. The increases in hepatic glucose 6-phosphatase and fructose diphosphatase activities induced by a diet high in sucrose do not occur in adrenalectomized rats.