[Sensitivity of hexokinase and glucokinase to hormonal action during hepatocarcinogenesis]

Effects of hydrocortisone and insulin on activities of hexokinase and its isoenzymes and on glucokinase activity were studied in hepatocarcinogenesis, induced in rats by diethyl nitrosamine. After administration during 7 days of hydrocortisone into normal rats the hexokinase was inactivated by 25% due to decrease in activity of the II isoenzyme. In this case activity of glucokinase was decreased by 38% in young animals and--by 23% in older animals. Insulin, administered within 2 days, caused no effect on the hexokinase activity but the glucokinase was activated by 177%. In hepatocarcinogenesis the effect of hydrocortisone on the hexokinase activity (II isoenzyme) was distinctly decreased and with development of tumors the hormone showed a negligible efficiency. Influence of insulin on the glucokinase activity in hepatocarcinogenesis was similar to the effect found in normal liver tissue.