Abstract
To determine the influence of circulating insulin antibodies on the pharmacokinetics of insulin, we examined 125I-monoiodoinsulin binding, total and free insulins and plasma glucose after rapid intravenous insulin injection (0.1 U/kg or 0.04 U/kg) in 12 diabetic patients. In the patients with insulin antibodies, 1251-monoiodoinsulin binding decreased to the lowest level immediately after insulin injection and returned to baseline by 120 min. In contrast, total and bound insulins of those patients increased to the maximum levels immediately after injection. Compared with diabetic subjects without insulin antibodies, diabetic subjects with antibodies had reduced initial increases in free insulin and late hyperinsulinemia. The plasma total insulin half-lives (T 1/2), which were determined by least squares regression computer program, showed apparent prolongation (40.2±5.1 min: 0.1 U/kg, 65.5±13.3 min: 0.04 U/kg) in the patients with insulin antibodies.
We conclude that moderate insulin antibodies in insulin-treated diabetics can bind insulin entering the circulation very rapidly and subsequently release it more slowly, resulting in late hyperinsulinemia and possible hypoglycemia.
