Susceptibility of different rat tissues to non-enzymatic protein glycosylation in experimental diabetes.

Hyperglycemia was induced in Sprague-Dawley rats by alloxan and maintained for 2, 6 and 10 weeks without insulin treatment. Levels of glycosylated plasma proteins, hemoglobin and glycosylated tissue proteins of aorta, heart, kidney, liver and brain were estimated at these intervals. Protein glycosylation was observed to increase linearly as a function of period of hyperglycemia in all the tissues studied, except brain, in the following order: aorta > heart > kidney > liver. Protein glycosylation, leading to formation of covalently modified advanced glycosylated products and protein-protein adducts, may reflect disposition of these tissues to diabetic complications.