Insulin binding to erythrocytes in children with type I diabetes mellitus before, and after insulin treatment.

125I-insulin binding to erythrocytes was studied in 24 children with type I diabetes mellitus before institution of insulin therapy, and in 10 normals. Mean specific 125I-insulin binding in the diabetics was significantly lower than in the controls (10.2 +/- 0.4% (SEM), as against 11.6 +/- 0.5%, P less than 0.05). In 8 diabetics the study was repeated after 3-6 weeks of therapy, at which time the insulin binding had increased to normal (12.1%, range 10.7-13.6). No correlation was found between insulin binding and blood glucose, plasma insulin or plasma beta-hydroxybutyrate. We conclude that insulin binding to the receptors is altered in the early phase of type I diabetes.