Abstract

In the adult rat, starvation during 48 hours led to a three fold increase of lactase specific activity in the intestinal brush border membranes. Thyroxine injection during the three days before death (0.5 micrograms/g daily) inhibited the stimulation of lactase activity induced by starvation without modifying sucrase activity whereas hydrocortisone injections (25 micrograms/g daily) or thyroidectomy did not modify the stimulatory effect of starvation on lactase activity. These results suggests a specific hormonal control of intestinal lactase activity in the rat.