Effect of oral doses of zinc oxide on the secretion of pancreatic juice and bile in sheep.

Three sheep were given zinc oxide three times a week for six weeks at a dose rate of 240 mg zinc kg-1. The pancreatic injury resulting from the zinc oxide dosing varied from minor to severe. There was a large reduction in the rate of flow of pancreatic juice and in the concentrations of protein and amylase in the pancreatic juice from the extensively injured pancreas. Before dosing with zinc oxide, the zinc concentration in pancreatic juice was greater than in bile and increased markedly after zinc oxide dosing commenced. After prolonged dosing, zinc concentrations and output in pancreatic juice varied inversely with the degree of pancreatic injury. The bicarbonate concentration in pancreatic juice was unaffected by the zinc treatment but total output was reduced in the most severely affected sheep because flow rate decreased. In this sheep biliary bicarbonate concentration but not total bicarbonate output was increased.