| Summary: | 碩士 === 國立臺北教育大學 === 體育學系碩士班 === 96 === Background and Objective： Hypoxia/reoxygenation has been known to cause oxidative damage in many tissues including several intracellular components of erythrocytes. However, the mechanism of reactive oxygen species (ROS) induced by exercise and/or hypoxia/reoxygenation remains unclear. The study was to investigate the interaction between erythrocytes and plasma in vitro w/o exhaustive exercise stimulus in condition of hypoxia/reoxygenation. Methods： Eight healthy men were included as subjects (28.9 ± 2.9 yr, 170.1±5.9 cm, 68.9±7.4 kg). Erythrocytes were separated form blood samples collected before and after exhaustive treadmill exercise. The reaction samples were then reconstituted considering: w/o leukocytes or plasma replaced by PBS or plasma before exercise replaced by that after exercise (and vise versa). Test samples were incubated w/o diphenylene iodonium(DPI) (5μM) or allopurinol (5μM) at room temperature in condition of normbaric normoxia, normbaric hypoxia and hypobaric hypoxia. Biochemical parameters were analyzed including: glucose, lactate, glucolytic rate, nitric oxide in supernatants; superoxide dimutase (SOD) activity, glutathione peroxidase (CPx) activity, catalase (CAT) activity, fragility in erythrocytes; thiobarbituric acid reactive substances (TBARS) in both supernatants and erythrocytes. Repeated measures of two-way ANOVA was used to analyze data and statistically significant level was set at p ≦.05 . Results：Exercise, rearrangements and treatments of allopurinol, DPI or hypoxia/reoxygenation appeared no effect on erythrocyte fragility, supernatant NO. Increased Hypoxia/reoxygenation increased supernatant lactate release mediated by leukocytes and erythrocyte GPx activity. Erythrocyte CAT activity was increased only in erythrocytes immediately after exercise. The erythrocyte glucolytic rate was inhibited by activated leukocytes and plasma. Substances of anti-lipid peroxidation existed in postexercised plasma and can protect erythrocyte from oxidative damages. Conclusions：Exercise decreased glucolytic rate in erythrocytes. Oxidative stress inside and outside of erythrocytes was increased by exercise, culture in vitro, and hypoxia/reoxygenation. Postexercised plasma provided erythrocyte of protection from oxidative damages. Antioxidants used in this study cannot decrease oxidative stress inside the erythrocyte.
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