THE EFFECT OF ACARBOSE ON DIABETES-RELATED AND AGE-RELATED BASEMENT-MEMBRANE THICKENING IN RETINAL CAPILLARIES OF THE BB W-RAT/

The effect of the alpha-glucosidase inhibitor acarbose on retinal capi llary basement membrane thickening was examined in the spontaneously d iabetic BB/W-rat. Four months of diabetes resulted in significant thic kening of the basement membranes of both the superficial and deep capi llary nets of the retina. This characteristic change of the retinal mi crovasculature in diabetes was completely prevented by acarbose treatm ent that substantially reduced postprandial hyperglycemia. A similar b ut less pronounced effect was seen on the age-related increase in base ment membrane thickening in acarbose-treated non-diabetic control rats who demonstrated decreased glycated hemoglobin levels compared to non -treated control rats. Significant positive correlations between basem ent membrane thickness and glycated hemoglobin area suggest that diabe tic retinal microangiopathy may be prevented by lowering the cumulativ e glucose exposure to the microvasculature, and that age-related basem ent membrane thickening is mediated by long-term exposure to normal gl ucose levels.