[Metabolism of capillary endothelium tissue and its abnormalities in diabetes mellitus (author's transl)].

Glucose is the major energetic substrate of blood capillary endothelium; aerobic glycolysis is quantitatively the most important pathway. Insulin has no direct effect on glucose utilization. The glucokinase activity of the capillary endothelium is undetectable and the plasma cell membrane is freely permeable to glucose. All pathways of glucose utilization are stimulated by a high ambient glucose concentration: intracellular sorbitol accumulation and glucose-carbon incorporation into basement membrane collagen are most sensitive to the glucose effect. During chronic hyperglycemia, the amino acid composition of the basement membrane is modified and its capacity to incorporate glucose is enhanced. The glucose induced alterations of the blood capillary metabolism may contribute to the development of the diabetic microangiopathy.