Abstract
Hepatic glucokinase (GK) and intestinal disaccharidase were assessed in growing rats.
Hepatic GK activity, not detectable upto day 16 after birth, was markedly enhanced after day 25 and reached toward the adult's level on day 30. This enzyme activity was not always suppressed by the administration of 17-β-estradiol which exerted tremendous changes of sexual organs in their weight.
Simultaneous administration of hydrocortisone acetate and glucose was found to be effective on a significant elevation of hepatic GK activity in the rats before weaning (day 22 after birth). Prior to the induction of hepatic GK activity, it was observed that both maltase and sucrase activities in the rat intestine were markedly increased and reached to the maximal levels on day 22 and day 26, respectively.
These findings strongly suggest that corticosterone plays a physiological and essential role in developmental formation of hepatic GK activity, which can be completed in the consequences of increasing supply of glucose to the liver and secretion of insulin from the pancreas, following a precipitous rise of intestinal disaccharidases in the course of weaning.
