Influence of Nitric Oxide Synthase and Kinin Antagonists on Metabolic Parameters in Chronic Streptozotocin-Induced Diabetes Mellitus

Abstract

In vivo administration of HOE 140 (a new bradykinin receptor antagonist) and L-NAME (Nitric oxide synthase inhibitor) was performed in chronic streptozotocin-diabetic rats. Basal increases (in umol.g dw⁻¹) in liver (45.0 ± 3.4.1) and uterine (40.0 ± 2.95) triglyceride levels in diabetic animals vs control (liver: 34.0 ± 3.87; uterus: 30.2 ± 4.01) were partially prevented by L-NAME (p < 0.01), HOE 140 (p < 0.01) and L-NAME + HOE 140 (p < 0.01). High glycogen levels (in mg.g dw⁻¹) observed in diabetic uterine tissue (3.07 ± 0.90), and decreased glycogen content detected in diabetic liver (11.64 ± 1.50) vs. control (uterus: 1.59 ± 0.15; liver: 17.25 ± 0.87) were unaffected. Uterine ¹⁴CO₂ production from ¹⁴C-U-Glucose (in uCi.mg dw), which is lower in diabetic (35.0 ± 5.12) than in control (50.12 ± 4.54) tissues, was improved by HOE 140 (p < 0.05) and L-NAME + HOE 140 (p < 0.05), while hepatic glucose oxidation was not increased by the drugs. Glycemia levels were decreased in diabetic rats injected with L-NAME and L-NAME plus HOE 140.

Pancreatic 6-Keto-prostaglandin F_1alpha to Thromboxane B₂ ratio was lower in diabetic animals than in controls, and L-NAME and/or HOE 140 treatment prevented the decrement. These findings suggest that vasoactive compounds might prevent streptozotocin-induced damage in pancreatic tissue from chronic diabetic rats.