Time-Dependent Alterations in Rat Macrovessels with Type 1 Diabetes

Vascular complications are associated with the progressive severity of diabetes, resulting in significant morbidity and mortality. This study quantifies functional vascular parameters and macrovascular structure in a rat model of type 1 diabetes. While there was no difference in the systemic arterial elastance (Ea) with 50 days of diabetes, changes were noted in the aorta and femoral artery including increased tunica media extracellular matrix content, decreased width of both the media and individual smooth muscle cell layers, and increased incidence of damaged mitochondria. Extracellular matrix proteins and elastin levels were significantly greater in the aorta of diabetic animals. These differences correlated with diminished matrix metalloprotease activity in the aorta of the diabetic animals. In conclusion, diabetes significantly altered the structure and ultrastructure of the aorta and femoral artery before systemic changes in arterial elastance could be detected.