Affinity hypoxia as a pathogenetic factor of microangiopathy with particular reference to diabetic retinopathy.

The microvascular complications in the retina and kidneys are preceded and accompanied by functional abnormalities. The appearance of the first retinal responses, venous dilatation associated with increased plasma permeation, suggest a state of tissue hypoxia located close to the venous microcirculation. Studies are summarized to indicate that diabetes is associated with a fluctuating disturbance in the oxygen release capacity of the erythrocytes. Combined with microrheologic alterations this fluctuating affinity hypoxia may over the years participate in the pathogenesis of the microvascular disease in diabetes.