The Effect of Chronic Exercise and Hypoxia on Glucose Transporter Expression in Adipose Tissue of Zucker Rats

• Main Authors: Lin, Fang-Chun, 林方春
• Other Authors: Kuo, Chia-Hua
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/97201294187915313661

碩士 === 臺北巿立體育學院 === 運動科學研究所 === 96 === The purpose of the study was to determine the combined effect of exercise and intermittent hypoxia on body weight, fat mass, and glucose tolerance in genetically obese rats. 36 obese Zucker rats (fa/fa) were weight-matched and divided into 4 groups: Control (N= 9), Exercise (N= 9), Hypoxia (N= 9), and Exercise+Hypoxia (N= 9). Same experiment was repeated in lean Zucker rats. For the exercise group, rats were swum for 3 h per day, 7 day a week for 6 weeks with a weight load of 3% BW. Weight load of 5% BW was used for the obese rats to counterbalance greater buoyant force during swimming (judged by achieving the same angle long vertical axis). For the Hypoxia group, rats were housed in a hypoxia chamber (14% O2) for 8 h per day, 7 day a week for 6 weeks. Exercise plus hypoxia, but not either treatment alone, significantly slowed down the body weight increases in both lean and obese Zucker rats. For both lean and obese rats, epididymal fat masses, serum leptin, leptin mRNA levels in both the Exercise and Exercise+Hypoxia groups were significantly lower than that in the Control rats. In contrast, GLUT1 and GLUT4 protein levels of lean rats were greater in both the Exercise and Exercise+Hypoxia groups above control. Improvement in glucose tolerance was only observed in the Execise+Hypoxia group. In lean rats, AMP protein kinase (AMPK) and AMPK phosphorylation levels, but not β-actin, were significantly greater in the Exercise and Exercise+Hypoxia groups above control. However, these increases were completely blocked in the obese Zucker rats. HIF-1α mRNA level was elevated only in the Exercise+Hypoxia group above control. The current study demonstrated that 1) combination of exercise training and hypoxia provided better effect on improving glucose tolerance and body mass compared to exercise and hypoxia alone; 2) Effects of combined treatment on the AMPK and HIF-1α was blunt in obese Zucker rats.