Streptozotocin-induced diabetes in rat. I. Influence of hypertension and myocardial infarction on the development of vascular complications.
Streptozotocin diabetes in rats was complicated by spontaneous hypertension (SHR) and myocardial infarction (MIC), considered as "risk groups". Renal function was assessed on the basis of blood urea nitrogen (BUN) and albuminuria. BUN increased by 36% in Wistar diabetic group, by 100% in SHR + diabetes, and by 51% in MIR + diabetes. Morphologic changes were assessed by estimation of PAS-positive glycosaminoglycans and measurement of vascular wall thickness of glomerular arterioles. The risk groups showed exaggerated tendency for development of diabetic angiopathy. A significant imbalance between TXA2 and prostacyclin was found, which was reflected by TXB2/6-keto-PGF1 alpha (the stable metabolites of TXA2 and prostacyclin, respectively) ratio, which increased by 38% in Wistar diabetic rats, by 61% in SHR + diabetes, and by 133% in MIR + diabetes. These changes correlated very well with increased platelet aggregability (r = 0.70; p less than 0.05) and with increased lipid peroxide level (r = 0.60; p less than 0.05), but neither with total plasma cholesterol (r = 0.20), nor with plasma triglycerides (r = 0.34). Lipid peroxides increased 5-fold in Wistar diabetic rats, 6-fold in SHR + diabetes, and 5.5-fold in MIR + diabetes. A causative relationship between TXA2/PGI2 imbalance and lipid peroxide changes on one hand, and diabetic angiopathy, on the other, was suggested.
Somova
L
L
Institute of Endocrinology and Gerontology, Bulgarian Medical Academy, Sofia.
Dashev
G
G
Kamenov
V
V
Kirilov
G
G
Kirjakov
A
A
Doncheva
M
M
Vassileva
M
M
D000818:Animals; D001808:Blood Vessels / Q000473:pathology / Q000503:physiopathology; D003921:Diabetes Mellitus, Experimental / Q000150:complications* / Q000473:pathology / Q000503:physiopathology; D003925:Diabetic Angiopathies / Q000503:physiopathology*; D006973:Hypertension / Q000150:complications*; D007668:Kidney / Q000473:pathology / Q000503:physiopathology; D008054:Lipid Peroxides / Q000097:blood; D008055:Lipids / Q000097:blood; D008297:Male; D009203:Myocardial Infarction / Q000150:complications* / Q000473:pathology; D010179:Pancreas / Q000473:pathology; D010974:Platelet Aggregation / Q000187:drug effects; D011460:Prostaglandins F / Q000097:blood; D051381:Rats; D011918:Rats, Inbred SHR; D011919:Rats, Inbred Strains; D013929:Thromboxane B2 / Q000097:blood
D008054:Lipid Peroxides; D008055:Lipids; D011460:Prostaglandins F; D013929:Thromboxane B2; C100006:prostaglandin F1