[Blood serum proteins in diabetes mellitus. Euglobulin level]

Some physicochemical and immunochemical properties of blood serum euglobulins were studied in patients with diabetes mellitus with different degree of vascular lesions. Euglobulins were isolated from blood serum of normal subjects and diabetes mellitus patients by precipitation in low ionic strength dialyzing solution. As a result two euglobulin subfractions were obtained: soluble and insoluble in an isotonic saline. To study euglobulins, use was made of radioimmunoassay, gel filtration, and radial immunodiffusion. The data obtained indicate that patients with diabetes mellitus showed a significant increase in euglobulin content in both subfractions (P less than 0.001). Besides, the insoluble subfraction demonstrated a new protein component with a molecular mass about 265000 dalton, uncommon to healthy donors. There was a dramatic increase (P less than 0.0001) in the amount of euglobulin bound insulin, an insignificant part of which was combined with insulin antibodies and greater part with unidentified euglobulin components. The changes in the physicochemical and immunochemical properties of serum globulins in diabetes mellitus patients correlated with the gravity of vascular lesions as regards the majority of the parameters. It is concluded that these changes are possibly involved in the pathogenesis of diabetic angiopathies.