Intravenously administered human epidermal growth factor in the rat. Biliary excretion and influences on pancreatic...

Epidermal growth factor (EGF) is known to exert mitogenic effects in different tissues, including the digestive tract and pancreas. EGF is also found in high concentrations in pancreas. Infusion of human EGF has been shown to induce proliferation of cells in exocrine pancreas, and to increase the thickness of the small intestine. The aim of this study was to investigate the influence of intravenously administered human EGF on pancreatic and biliary secretions in the rat.

Rats were fasted overnight and were given human EGF intravenously, either as a bolus dose of 5 microg or as a continuous infusion in increasing doses from 0.5 to 10 microg/h. Bile and pancreatic juice were either collected together or separately. The concentration of human EGF in bile and pancreatic juice was measured.

After a bolus dose of EGF increased bile/pancreatic secretion was seen after 60 and 90 min when the bile and pancreatic secretions were not separated. Continuous infusion of EGF increased the joint secretion rate of bile and pancreatic juice in a dose-dependent manner. No effect on secretion rate was seen when bile and pancreatic juice were collected separately. After intravenous infusion of human EGF a 1,000-fold increase of human EGF excretion was found in bile but not in pancreatic juice.

Intravenously administered human EGF was excreted in high concentrations in bile and increased the secretion rate of pancreatic juice when collected together with bile. The results suggest that EGF, at least partly, exerts its effect on the pancreas and the proximal gastrointestinal tract after excretion with bile and stimulates pancreatic secretion via this route.