LOW DIETARY IRON RESTORES FUNCTIONAL CAPABILITIES OF BOTH EXOCRINE AND ENDOCRINE PANCREAS IN COPPER-DEFICIENT RATS

Copper deficiency is associated with a selective atrophy of the pancre as. Copper deficiency is also associated with hepatic iron retention. In the past, we have shown that the reduction of dietary iron prevente d the pathologies of the pancreas in copper-deficient rats. The presen t study was designed to determine whether the reduction of dietary iro n in copper-deficient rats would alleviate functional disturbances of the endocrine and exocrine pancreas. Weanling male rats were fed a cop per-deficient (0.6 mu g Cu/g) or adequate (6.0 mu gCu/g) diet containi ng either adequate (50 mu g Fe/g) or low (17 mu g Fe/g) iron for 4 wee ks. Rats were killed following an overnight fast. Insulin, amylase and lipase were measured in pancreatic tissue. Copper-deficient rats fed the adequate-iron diet exhibited extremely high levels of insulin but low activity of amylase and lipase. Once the intake of dietary iron wa s reduced, levels of pancreatic insulin and activity of digestive enzy mes returned to normal. Lowering intake of dietary iron resulted in re duction of liver and pancreas iron but caused an expected increase in copper concentrations. Low iron was also associated with reduction of lipid peroxidation. It is suggested that reduction of free radicals wa s responsible for restoring the ability of the endocrine pancreas to r elease insulin, which in turn stimulated the exocrine pancreas to synt hesize digestive enzymes. (C) 1997 Wiley-Liss, Inc.