1 Department of Pediatrics, Ehime University School of Medicine, Shigenobu, Ehime 791-02, Japan
The quantitative relation between insulin binding to circulating monocytes in vitro and glucose tolerance in obese children in vivo is reported. Sixty-one obese children and 11 healthy control children participated in this study. The oral glucose tolerance test (OGTT) was performed by giving them glucose (1.75 gm/kg of body weight), orally in the morning, and the binding of 125I-labeled insulin to circulating monocytes in vitro was measured prior to OGTT. The glucose tolerance expressed by
BS (milligrams/100 ml), the sum of the plasma glucose (blood sugar [BS]) values at OGTT, was significantly correlated with the degree of overweight (r = .316, P < .01) and more highly with
IRI (microunits per milliliter), the sum of immunoreactive insulin (IRI) values at OGTT (r = .512, P < .001). Insulin binding to monocytes in vitro (picograms/106 cells) was inversely correlated with the degree of overweight (r = -. 687, P < .001). Furthermore,
BS was inversely correlated significantly with insulin binding to monocytes in vitro (r = -.435, P < .002). These data suggest that the decrease of insulin receptors might be one cause for the impairment of the glucose tolerance associated with obesity in children.