Affiliations: Department of Physiology, Faculty of Medicine, Srinakharinvirot University, Bangkok 10110, Thailand | Department of Physiology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand | Department of Vascular Physiology, National Cardiovascular Center Research Institute, Osaka 565‐8565, Japan
Abstract: The effect of long‐term supplementation of vitamin C on leukocyte adhesion to the cerebral endothelium was investigated in streptozotocin (STZ)‐induced diabetic rats. Diabetes was induced in male Wistar Furth rats by intravenous injection of STZ. The vitamin C, ascorbic acid, was supplemented with drinking water (1 g/l). The rats were divided into control and diabetic groups without or with supplementation of vitamin C. The cerebral microcirculation was directly observed through a cranial window after different periods (12, 24 and 36 weeks) of vitamin C supplementation, using fluorescence videomicroscopy. Leukocyte adhesion to the venular endothelium was examined by labeling leukocytes with rhodamin 6G. The number density of adherent leukocytes in STZ‐diabetic rats was increased singnificantly, compared with control rats. This increase in leukocyte adhesion was prevented by the long‐term supplemented vitamin C. It was suggested that the antioxidant effect of vitamin C might be responsible for the prevention of leukocyte adhesion in diabetes mellitus.
