We have studied insulin binding to erythrocyte receptors in a group of 25 nonobese,
nondiabetic uremic patients undergoing maintenance hemodialysis for 2-54 months and
14 healthy controls. Erythrocytes of predialyzed uremics bind significantly less insulin
than control erythrocytes (p < 0.01). Dialysis resulted in a rapid increase of insulin
binding (p < 0.001). The concentrations of plasma insulin and glucose remained essentially
unchanged during 5-hour hemodialysis and did not significantly differ from the control
values. The down regulation of insulin receptors in undialyzed patients in the presence
of normal plasma insulin concentration indicates that factors other than insulin itself
could be responsible for insulin receptor activity during uremia. The results demonstrated
that creatinine, creatine and glycocyamine have a direct suppressive effect on insulin
binding of postdialyzed plasma (p < 0.05) in concentration of 1 mmol/l. This suggested
that specific uremic toxins could play an important role in the mechanisms of altered
insulin binding during hemodialysis. Despite the high concentration of these compounds
in blood of uremics, the only common feature for these compounds is the presence of
the guanidino group in the molecule.
Insulin Binding - Uremia - Uremic Toxins - Creatine - Creatinine - Glycocyamine
