Impaired elastic properties of the aorta in fat-fed, streptozotocin-treated rats. Vascular remodeling in diabetic arteries.
BACKGROUND
Vascular complications associated with diabetes are the major cause for the increased morbidity and mortality in diabetic patients. However, the progression of vascular complications in diabetes is not well understood. We aimed to investigate the biomechanical and biochemical changes associated with vascular dysfunction in diabetic rats.


METHODS
Male Wistar rats were randomly divided into two groups: normal control (n = 8) and fat-fed, streptozotocin-treated diabetic rats (n = 11). After 16 weeks, Peterson's modulus of elasticity (Ep) and cross-sectional distensibility (CD) were calculated and compared between the two groups. Aortas were harvested from rats for histopathological and electron-microscopic analysis.


RESULTS
Collagenous fibers were scattered in the extracellular matrix and invaded the elastic lamina in the aortas of diabetic rats, suggesting a significant accumulation of collagen in diabetic vessels. Compared with normal rats, diabetic rats showed significantly reduced aortic distensibility (CD: 0.10 +/- 0.04 vs. 0.17 +/- 0.08 kPa(-1), p = 0.033) and an increased aortic stiffness index (Ep: 0.25 +/- 0.13 vs. 0.15 +/- 0.05 x 10(6) dyn/cm(2), p = 0.045). Ep was positively and CD negatively correlated with glucose and collagen in diabetic rats.


CONCLUSIONS
In diabetic rats, elastic properties of the aorta are impaired, being closely related to hyperglycemia-induced vascular wall remodeling.
Sun
Hui
H
Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Public Health, Shandong University, Qilu Hospital, Ji'nan, China.
Zhong
Ming
M
Miao
Ya
Y
Ma
Xiao
X
Gong
Hui-Ping
HP
Tan
Hong-Wei
HW
Zhang
Yun
Y
Zhang
Wei
W
D000818:Animals; D001013:Aorta, Thoracic / Q000473:pathology*; D001786:Blood Glucose / Q000032:analysis; D003921:Diabetes Mellitus, Experimental; D003925:Diabetic Angiopathies / Q000473:pathology* / Q000503:physiopathology; D004041:Dietary Fats / Q000009:adverse effects*; D004195:Disease Models, Animal; D004548:Elasticity / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D016014:Linear Models; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000473:pathology; D011336:Probability; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012016:Reference Values; D012680:Sensitivity and Specificity; D013311:Streptozocin / Q000494:pharmacology; D014655:Vascular Resistance / Q000502:physiology
D001786:Blood Glucose; D004041:Dietary Fats; D007328:Insulin; D013311:Streptozocin