Insulin treatment prevents vascular dysfunction in early juvenile alloxan-induced diabetes mellitus

Microvascular pathology and sympathetic autonomic dysfunction have been described early in alloxan-induced diabetic juvenile rats. To determine the longitudinal development of these changes and whether insulin treatment can alter them, vascular and sympathetic function were studied in alloxan-induced (42.5 mg/kg) juvenile diabetic rats and saline-treated controls. The rats were examined 1 and 14 days after induction of diabetes. An insulin-treated group was studied with the 14-day group. Hindquarter perfusion with an artificial solution at constant flow/100 g hindquarter wt was used. After 14 days of diabetes mellitus, the diabetic group showed a significantly depressed response to central ischemia (P less than 0.001), maximal vasoconstriction (P less than 0.02), and maximal dilation (P less than 0.001) compared with both the control and insulin-treated group. The threshold response to norepinephrine did not differ. After 1 day of glucose elevation no differences were present between the control and diabe...