Changes of mesenteric microcirculation in chronic diabetic rats: A pilot study using intravital fluorescence microscopy

In this study, we investigated the changes of mesenteric microcirculation in chronic diabetic rats (36-wk) using intravital fluorescence microscopy. Blood glucose, HbA(1C) and mean arterial blood pressure were significantly higher in diabetic rats when compared with control rats. After precontraction with norepinephrine, the vasodilation responses to sodium nitroprusside (10(-6) M) of both diabetic and control groups were no significant difference. However, the vasodilation response to acetylcholine (10-6 M), an endothelium-dependent vasodilator, was significantly less in diabetic arterioles than in control vessels (p<0.05). In addition, the leukocytes adhesion on diabetic venules were significantly increased than those of control (p<0.05). Therefore, this study demonstrates that chronic diabetic rats is associated with endothelial dysfunction which is manifested as an impaired endothelium-dependent relaxation in mesenteric arterioles and an increased leukocyte adhesion in mesenteric venules.